SUPPORTED BY
MAY 2015
A HOUSING FORUM WORKING GROUP REPORT INTO
HOW MODERN METHODS OF CONSTRUCTION CAN
DELIVER MORE AND BETTER QUALITY HOMES
2
Contents
The Housing Forum
The Housing Forum is a membership
network of organisations and
businesses which collaborate to
develop and improve the nation’s
housing stock. The Housing Forum is
the only cross-sector, industry-wide
membership network that represents
the entire housing supply chain on
behalf of the housing industry.
We have over 120 member organisations,
from both public and private sectors,
collaborating to inform, influence
and network. The views in this report
are the views of The Housing Forum
and have been contributed from Working
Group discussions and round table
forums with senior and leading
housing industry figures.
www.housingforum.org.uk
More Homes Through Manufacture
A Housing Forum Working Group Report
The Hyde Group
The Hyde Group is one of the
UK’s leading and award winning
providers of housing and a
member of The Housing Forum.
It operates in London, the South East,
the East of England and the East
Midlands providing homes with a variety
of tenures. The Hyde Group houses
95,000 residents in 49,000 homes.
www.hyde-housing.co.uk
47
2015/16
Working Groups
Kevin Reed,
UK Specification Manager, Graf
UK Ltd
Geoff Reynolds,
Senior Development Manager,
Kier Living
Robin Roberts,
Property Services Director,
Worthing Homes
Gordon Ronald,
Operations Director, Fusion21
Chris Rutter,
Business Manager, Fusion21
Manjit Sanghera,
TEK and UNIDEK Product
Manager, Kingspan Insulation
Dennis Seal,
Executive Director, Buildoffsite
Steve Skuse,
Pre-Construction Director,
Willmott Dixon
Alex Thomas,
Key Account Manager, Worcester
Bosch
Keith Trowers,
Senior Business Development
Manager, Durkan
Jon Wardle,
Director, Airey Miller
Construction Management
Joy Whinnerah,
Major Projects Manager, Home
Group
Richard Wilks,
Technical Advisor, Aggregate
Industries
Chris Wisson,
National House Developer
Manager, Marshalls
Topic Presenters to the Working
Group on Offsite Manufacture
and Supply Chain Innovation:
Rory Bergin,
Partner, Sustainable Futures,
HTA Design LLP
Mark Bradbury,
Development Consultant,
Climate Energy Homes
Graham Clarkson,
Director, The Clarkson Alliance
Stewart Hackney,
Business Development
Manager, Fusion Building
Systems
Jack Kennedy,
Construction Director, Charcon
Construction Solutions
Working Group support:
Shelagh Grant,
Chief Executive,
The Housing Forum
[email protected]
Laura Waind, Membership &
Development Manager,
The Housing Forum
[email protected]
The Housing Forum is
grateful to The Hyde
Group for supporting the
report and facilitating this
examination of the role of
OSM in contributing to the
debate on housing supply.
With special thanks to David
Gannicott, Group Director of
Business Development and
Simon Vevers, New Business
and Strategy Director at The
Hyde Group.
Printed by Hartgraph Ltd.
The Housing Forum Working Groups produce
influential reports for our members, which
are recognised at the highest levels in
Government and throughout the industry.
The topical agendas continue to draw in
external specialists from finance, planning,
Government and trade associations.
Member organisations can join any Working
Group and to register your interest in
participating, please contact Shelagh Grant
or Laura Waind.
[email protected]
[email protected]
SUPPORTED BY
More Homes Through Manufacture
A Housing Forum Working Group Report
Contents
Contents
04
Foreword
David Lunts, Executive Director of Housing
and Land at the Greater London Authority
on the challenge to build more homes for
London
06
Introduction
Shelagh Grant, Chief Executive, The Housing
Forum and David Gannicott, Group Business
Development Director, The Hyde Group
08
Why housebuilding is changing
Innovative solutions needed to help
solve the housing crisis
16
Why wouldn’t you buy a factory home?
HTA Design Partner, Rory Bergin
runs through all the advantages
18
Living in a factory made home
Residents describe what it’s like
24
From feeding the cat to ordering food
Jim Martin, Senior Partner, Martin Arnold,
explains why homes are set to get smarter
26
Transforming construction
Housing schemes around the
country built offsite
42
The digital revolution
Andy von Bradsky, Chairman, PRP,
on integrating digital technology
and offsite prefabrication
44
Concluding remarks
Weighing up the benefits
46
Credits
3
4
Foreword
More Homes Through Manufacture
A Housing Forum Working Group Report
Foreword
David Lunts
Executive Director
of Housing and
Land, Greater
London Authority
and observer
to The Housing
Forum Board
We need to build a lot more homes and we need to build
differently to do so. That is obvious when you look at the
challenges we face in seriously stepping up supply. Land
shortages, skills shortages and materials shortages are all
massive constraints and each points to the need for a step
change in ways to deliver new housing - not least in embracing
faster, better and more modern methods of construction
(MMC), the benefits of which are highlighted in this report.
But is the industry ready to embrace the new? It certainly
won’t be easy. Some of the methodology is still unproven at
scale and the jury is still out over cost efficiencies, for example.
But if we are serious about increasing the rates of house
building - and to do so over the long term - we need to work
harder to make this step change possible. There is certainly
a role for the public sector to help in sponsoring and leading
this change. It could, for example, become a condition to use
responsible modern methods of construction as a condition of
building on public land, and grant funded housing associations
could come together to use their collective buying muscle to
provide a steady pipeline of opportunities for manufacturers
to invest in production technologies at scale. The new Housing
Zones too, which have recently been launched to accelerate
new housing in regeneration areas, could also provide useful
opportunities to support MMC at scale.
The industry is slowly adapting to new construction
techniques and this should be welcomed. But far more can be
done, and needs to be done, to embrace change at scale if we
are to ramp up home building to the levels we need.
This report is a useful and timely signpost in that journey.
5
The Oval Quarter.
South London,
built using modern construction
methods (see
page 29)
6
Introduction
More Homes Through Manufacture
A Housing Forum Working Group Report
Introduction
Shelagh Grant,
Chief Executive
The Housing
Forum
Housebuilding is changing. An urgent need for more homes,
coupled with a shortage of those skilled in traditional trades,
is driving housing innovation. Encouraged by Government,
housebuilders and housing associations are turning to more
modern methods of constructing homes, increasingly building
key components in factories and assembling them on site.
Our aim at The Housing Forum – which draws expertise from
all those involved in design, building and developing housing –
is to help build more and better homes and that is why we are
delighted to work with one of the leading housing providers,
The Hyde Group, to explore, capture and celebrate these
exciting developments in housebuilding.
The Housing Forum, in its 2015 Call for Action, said, “Britain
urgently needs a new strategy to build more homes, invest in
the existing housing stock and overcome a capacity and skills
deficit which is threatening to create a barrier to increasing
supply. But we must ensure that increasing output is not at the
detriment of quality. If we are to leave a lasting legacy for future
generations, we must innovate to drive the highest standard of
design and performance in new and existing homes.”
We don’t pretend for one second that offsite technology is
the only answer to solving the housing crisis, but it can play a
much greater part and should be developed and nurtured. The
resulting homes can be of a higher quality, more comfortable
and warmer than traditionally constructed homes, and of
course, built far more quickly.
This report provides a useful commentary on new types of
construction for housing, dispels a few misconceptions and
advances the debate on how offsite manufacture can move
into the mainstream.
We hope consumers and housing professionals alike will find
it useful, interesting and inspiring.
7
Homes in Coventry
built for Orbit housing
association using
factory-built timber
frame panels
(featured on page 18)
Hyde and
modular
construction
David Gannicott, Group Director
of Business Development,
The Hyde Group
We believe that
modern methods
of construction,
in the form of
modular or offsite
building, has the
scope to reduce
build costs and
improve quality
standards. Hyde
has ambitions to
deliver at least
one such scheme
during 2015/16.
Given the
shortage of
labour skills
especially in
London and the
South East, we
are keen to work
with contractors
using modern
methods of
construction,
especially on
low cost rented
or schemes
for the private
rented sector.
In fact, we have
designed our
new contractor
framework
to encourage
modern methods
of construction.
We are delighted
to be working with
The Housing Forum
in its research to
promote modern
methods of
construction as
we believe that all
of the economic
factors are in
place to make it a
success this time
round.
8
How House Building is
Changing and Why
More Homes Through Manufacture
A Housing Forum Working Group Report
HOW
HOUSEBUILDING
IS CHANGING
AND WHY
SKILLS SHORTAGES AND GREATER ENERGY
EFFICIENCY ARE DRIVING INNOVATION
University
accommodation, like
these new Mayflower
Halls at the University of
Southampton are built
using prefabricated
components, and
housebuilding is
beginning to follow
9
10
How House Building is
Changing and Why
More Homes Through Manufacture
A Housing Forum Working Group Report
he number of new homes being built in the
last few years has fallen to the lowest on record
– fewer than half the number the UK needs to
be producing to reduce housing shortages and
bridge the huge affordability gap. A survey from
the National Housing Federation last year pointed
to the consequences – three out of 10 parents
have at least one adult child, aged between 21 and
40, still living with them at home, mostly because
their son or daughter cannot afford to rent or buy
their own place.
But as housebuilders and housing associations
begin to increase the building of new homes
they are turning to more modern methods of
construction to build faster, to higher standards,
and to enable them to comply with more stringent
demands for greater energy efficiency and
therefore lower energy bills.
While housebuilding has remained persistently
traditional, in that the most common building
method involves using a structural inner skin of
concrete blocks covered in an outer skin of brick,
we are increasingly seeing an array of factoryfabricated components even in traditionally built
homes, such as timber roof trusses and timber
frame walls. Many other building types – from
student accommodation to offices to schools
and hospitals – have been using more and more
components produced in factories and assembled
on site.
Housebuilding is now increasingly turning to
offsite manufacture for a number of reasons:
>Offsite methods offer advantages in terms of
speed of construction on site, quality of build,
sustainability and reduced health and safety
risks. Less labour and fewer materials and
deliveries are needed on the construction site,
meaning a reduction of noise, disruption, dust
and waste created for the local area.
>Increasing the energy efficiency of new homes
through tightening requirements of Part L of
the building regulations is another key driver. It
will become more difficult and therefore more
expensive to deliver through traditional forms of
construction.
>Skills shortages – according to Offsite
Housing Review, housebuilders said that to
increase build capacity to more than 140,000
homes a year they would need to turn to
some form of offsite1. Build rates of 230,000 a
year are needed to meet demand. A shortage
of traditional tradespeople like bricklayers –
and the recent shortages of bricks – has also
pushed up prices of building in a traditional
way, so that offsite methods are more
commercially viable2.
>Offsite manufacture dovetails with the needs
of those developing for private or social rent
where the financial model relies on faster
construction and occupation.
At the moment, about 90 percent of all new
housing in England and Wales is constructed
using masonry – brick and block. The inner
skin provides the structural walls that bear
the load of the intermediate floors and roof
above. Blockwork, set in mortar, has been the
11
Light weight steel frames,
as used by Osborne to build
Brunel Hall, a low cost housing
scheme for Crawley Borough
Council, are becoming increasingly popular in housebuilding
Using Fusion Building
Systems offsite technology meant that
this student accommodation for Oxford
University could be
delivered quickly
most popular way of building homes in
England and Wales since the 1930s. The
work is traditionally done by bricklayers,
who build both inner and outer skins of
the cavity wall. Much of the remaining
10 percent of new housing uses timber
frame (which accounts for about 70
percent in Scotland). The small remaining
portion is built using what are known as
Modern Methods of Construction (MMC)
where a significant proportion is built
in a factory. Timber frame construction
is very well established and considered
more or less traditional, even though
much is factory made.
Masonry construction has remained
the most popular for a number of
reasons, but a lot of it is to do with
costs. It’s been more economical.
But as labour costs have risen and
traditional construction has become
more expensive, the balance is
tipping, particularly as demand rises
for alternative methods. As factory
production is scaled up, it is anticipated
that costs of building using offsite
prefabrication construction will fall. That’s
not to say it’s a foregone conclusion with
housebuilders still preferring traditional
construction for a number of reasons,
which we’ll get on to later.
However, the Government is certainly
encouraging greater use of offsite
construction to increase housebuilding
and recently awarded a £22m grant to
a major construction company, Laing
O’Rourke, to invest in new technology.
The contractor’s offsite ‘kit of parts’
construction system, Design for
Manufacture and Assembly (DfMA), was
used to deliver the Leadenhall Building,
also known as The Cheesegrater, in
the City of London. It was also used
to build around 70 percent of the UK’s
first privately funded council housing
Why investor L&G
is backing offsite
construction
—
Legal & General has invested
over £1 billion in building new
student accommodation over
the last three years and
has used a variety of offsite
manufactured components in
the new buildings, including
bathroom pods. It is now
looking to use this building
method as it extends its
property portfolio into the
private rented sector. It
aims to grow this portfolio
to well in excess of £1bn over
the next five years across
the UK. James Lidgate,
Head of Residential, at
L&G says: “We’re keen to
harness modern methods of
construction for a number of
reasons; it provides better
quality, and meets higher
sustainable credentials
whilst delivering lower
operating and lifecycle
costs.” It has committed
plans to date for £200m of
development, with buildings
set to be between four and 10
storeys. Professor John Miles, University of Cambridge and
Professor Nick Whitehouse
Oxford Brookes University,
Offsite Housing Review,
February 2013, commissioned by Department for
Communities and Local
Government, published by
the Construction Industry
Council
2
According to a report by
accountants KPMG and
the London Chamber of
Commerce and Industry
(LCCI), about 20% more
construction managers,
surveyors, electricians and
other trades will be needed
to meet demand, over
the next four years, than
were needed from 2010-13.
November 2014
1
12
How House Building is
Changing and Why
More Homes Through Manufacture
A Housing Forum Working Group Report
scheme in Barking and Dagenham. Laing
O’Rourke has ploughed millions into developing
its prefabrication factory near Worksop, which is
currently developing DfMA prototypes that utilise
more lightweight modular steel frames and a
range of alternative cladding options3.
Elsewhere, procurement organisation
Procure Plus is planning to create the first
http://www.constructionmanager.co.uk/news/laingoffsite factory dedicated to social housing,
orourke-ramp-offsitewhich could see up to 1,000 homes produced in
solution-housing-crisis/ (
July 2014)
the North West of England each year from 2016. http://www.insidehousing.
co.uk/sectors-first-houseAccording to a report in Inside Housing
building-factory-movesstep-closer/7008182.
magazine4, Procure Plus has engaged
article?adfesuccess=1
consultants to assess the viability of
(February 2015)
http://www.insidehousing.
developing the pre-fabrication assembly
co.uk/development/sociallandlords-increase-use-ofplant, which would cost £2-3 million to
offsite-methods/7008558.
construct, to produce homes for the 40 local
article ( March 2015)
3
4
5
housing associations that form its client base
in the North West. The magazine reported that
the project is being monitored by the Homes and
Communities Agency, which wants to increase
offsite construction as part of its 2015-2018
affordable homes programme. Inside Housing also
published a survey in March 2015 which found that
15 out of 17 major housing associations intended
to increase their use of offsite construction,
including timber frame and modular builds5.
The 17 associations together have a
development pipeline of 22,544 homes over the
next three years, for which 57 percent will utilise
“offsite techniques”. Most of the associations
cited advantages in terms of cost, build quality,
speed of delivery, fewer weather delays, improved
energy-in-use and smaller carbon footprints.
The different types of offsite manufacture
—
Offsite manufacture is a
catch-all term to describe
technology where a
component or a significant
proportion of a house is
built away from the site –
usually in a factory. From
the outside, homes built
using these techniques
may not look any different
to traditional homes, as
they may still be clad in a
brick ‘slips’.
Volumetric: These units are
3D modules assembled in a
factory. The term ‘modular’
or ‘pods’ is used to describe
load-bearing units. The
main market for volumetric
is for closed modules. One
of the main advantages is
that these can be whole
rooms that come fully
plumbed and wired which
are transported to site and
stacked on top of each other
on ready laid foundations,
to form the building.
This method is popular
for highly standardised
accommodation such as
hotels, student residential
halls and care homes and
flats in urban medium and
high rise situations. Mar City
is a developer which uses
steel framed volumetric
units which are fully kitted
out with kitchens and
bathrooms and transported
to site.
The modular units
or pods may just be
bathrooms. With pods
the big advantage is that
services installation is
transferred into factory
engineered conditions.
For example, more than
30 trade activities are
transferred off-site
when bathroom pods are
used. This leads to fewer
people on site, easier
commissioning and less
rework.
Panellised: Increasingly
popular in the construction
of housing is the use
of panellised systems.
These systems involve
the on-site assembly of
flat panel walls to form
the internal load bearing
element, and cassette
floors (again a floor panel)
and roofs. Systems range
in complexity from simple
timber or light steel panels
(open), or concrete panels
and cassettes, to more
complex factory-finished
units incorporating
insulation, lining, doors,
windows and services
distribution (closed
panels). Closed panel
construction is the logical
step up from standard
open timber frame
manufacturing, as the
insulation, plaster board
and electrical systems
are installed offsite within
the panels before delivery
to site allowing the unit to
be wind and watertight in
one day.
A major innovation in
recent years, which is
increasingly being used, is
structural insulated panel
systems (SIPS), where
the rigid insulation core is
bonded to sheet linings to
form the panel.
Cross-laminated timber
(CLT) is also starting
to make its mark. CLT
panels normally form
the structural floor and
wall element of buildings,
and have been used
successfully to build up
to nine storeys in the
UK. It is typically used
in offsite manufactured
panels delivered to site
for erection via crane.
Cross-laminated is formed
in a similar fashion to
the more familiar gluelaminated timber beams
(‘glulam’), using small
sections of timber bonded
together with permanent
adhesives with the grain
perpendicular, resulting
in structural strength
across two dimensions,
and improving structural
integrity and dimensional
stability.
As well as aiding speed
of construction panellised
systems offer flexibility
in terms of layout and
room size. The integration
of Building Information
Modelling in the production
of systems, including
those supplied by Fusion
Building Systems, has
enabled a degree of
mass customisation to
be achieved at relatively
low volumes – giving
housebuilders greater
flexibility. Fusion Building
Systems Business
Development Manager,
Stewart Hackney, told
The Housing Forum that
lightweight gauge steel has
been gaining in popularity
because it does not settle
or shrink and provides
a better thermal and
acoustic performance.
Housing can be
constructed from hybrids
of modular and panellised
systems. The Housing
Forum’s view is that it is
essential to ensure that
appropriate technology
is chosen for appropriate
sites.
13
Jim Martin, Senior Partner, Martin Arnold, who
chairs the The Housing Forum’s Working Group,
Smarter Supply: Smarter Resources, says: “MMC
invariably produces higher quality, because these
homes are built under cover in benign conditions.
A year ago, using offsite systems was more
expensive, but this year the cost is the same.
However, these systems bring the benefit of
speed, and by next year they could be cheaper.”
The sentiment is echoed by contributors to our
technical case studies beginning on page 27.
Though rising costs of labour and materials,
coupled with increased capacity and Government
support, is helping drive momentum for more use of
offsite manufacturing, there are still barriers to be
overcome for the various technologies to become
mainstream amongst the major housebuilders.
The Offsite Housing Review found that there were
a number of factors holding offsite back, views
shared by members of The Housing Forum, who
have been discussing how offsite manufacture can
become more mainstream in housebuilding.
These include:
Who pays upfront costs for the factory units.
Procuring units fabricated in the factory requires
upfront payment, which runs counter to traditional
practice in that housebuilders will generally
subcontract a lot of the work and then pay for it
after it’s been completed.
Public perception of poor quality product.
Historic problems have blighted the
‘prefabrication’ brand.
There is concern about systematic failure. Just
because it’s been built well in the factory does not
mean the units will be put together well on site.
And if there is a problem, this could be amplified.
Confidence in the product and process. While
system certification is addressing concerns
of insurers and funds and mortgage providers,
product life and whole life performance continue
to be major concerns.
The Meadows, Essex
University built by
Bouygues UK.
Images by Hufton+Crow
Offsite manufacture in university accommodation
—
Offsite prefabricated
units have long since
been used in university
accommodation
for students; they
provide examples for
housebuilders to learn
from. Mayflower Halls
(shown on page 8 and
9) at the University of
Southampton comprises
three residential tower
blocks over a 1.5 acre
site reaching up to 17
storeys high, positioned
around a central piazza.
The £42.6m scheme was
completed in September
2014 in 20 months and
was constructed using
reinforced concretre
frame with SIP infill
panels. 8,000 plus
square metres were
installed per week of
programme. Principal
partners: Architecture
PLB (architects),
Osborne (contractor),
Innovaré Systems
(designer), Innovaré
Systems (manufacturer)
and the University of
Southampton (client).
The Meadows,
at the University of
Essex in Colchester
(shown above), is a
15,826 sq m student
complex providing
accommodation for 648
students. It comprises
19 town houses for 228
students plus ensuite
cluster flats for a further
420 students. There is
also a social pavilion
housing a common
room, a launderette and
a convenience store. The
total cost was £23m with
an average cost per unit
of £35,000. Completed
in September 2013, a
mixture of construction
techniques were used
– including ensuite
bathroom GRP pods, in
situ concrete frame (three
blocks – five to seven
storeys high) and timber
frame townhouses.
The developer was
Uliving, a consortium
made up of Bouygues
Development, housing
provider Derwent Living
and investment company
Equitix. Principal
partners: Bouygues UK
(contractor), Lewis &
Hickey (architect), MLM
(structural consultant),
Kane Heating (mechanical
contractor) and INEO
(electrical contractor),
Altor (pods supplier) and
Stewart Milne (timber
frame manufacturer and
installer).
14
How House Building is
Changing and Why
More Homes Through Manufacture
A Housing Forum Working Group Report
Bathroom pods
arrive on site for the
Riverlight development
in Vauxhall, London
(see case studies page 36)
Development of new skill sets. Clients and
project teams need to understand the properties
and constraints of the selected system and the
revised project process. The whole project team
also needs to collaborate effectively.
EU procurement rules make it difficult to get
an offsite supplier involved earlier on in the
process. That said, cost is often a determining
factor in choosing the form of construction and if
production could be increased and with it costs
lowered, the balance could tip more favourably in
offsite’s favour.
To increase demand, an incoming Government
could use plans for new garden cities to promote
offsite manufacturing to build homes. That way,
demand would increase and encourage more
investment, which could bring down costs.
Another suggestion is for Government to
stipulate that publicly owned land being sold for
development could include an element of offsite
construction. However, there are fears that this
would depress the sale price and be impractical to
enforce.
With growth anticipated in both housing and
public sector construction, offsite manufacture
is expected to play an important role in providing
additional capacity.
15
De-bunking myths about factory manufactured housing
—
Getting a mortgage
In the past it has
sometimes proved difficult
to obtain mortgages and
insurances on homes
built in a non-traditional
way. This was due in
part to the relatively
poor track record of past
generations of nontraditional construction.
Attitudes have changed
somewhat as products
have improved and
certification systems
put in place which can
demonstrate quality and
longevity. The Council of
Mortgage Lenders (CML)
says on its website: “While
lenders have no intrinsic
preference for any
particular mode of
construction, they do
have one overriding
requirement: that
properties considered in
relation to a mortgage
must be capable of
standing as security for a
loan of up to 35 years.”
Says the Council: “In
practice, this means that
the property must be
saleable and maintain, or
increase, its value over the
term of a mortgage loan.”
In relation to modern
methods of construction,
lenders have been
concerned about the
ability of some designs to
meet this criterion in key
respects:
—Durability: achieve a
design life of at least 60
years.
—Whole life costs at
a level comparable
to traditional
construction:
particularly relevant
for lenders to social
housing providers.
—Repairability: no undue
repair costs, and ability
to use a range of local
repair services.
— Adaptability:
the property
should, without
difficulty, support
the usual range
of adaptations/
extensions such
as a porch and
conservatory.
—Insurability: buildings
insurance should be
available on normal
terms.
The CML flags up a
number of certifications
systems including those
from the British Board of
Agrément (BBA), the BRE
and BOPAS. In addition,
following a rigorous
technical assessment
to ensure fit for purpose
and a 60-year design life,
the NHBC will provide
a 10-year warranty for
non-traditionally built
homes. Given this is
the leading new build
warranty scheme in the
UK, developments that
have this warranty are
unlikely to struggle for a
mortgage, nor should an
owner struggle to sell on,
says the NHBC’s Head of
Standards and Technical,
Graham Perrior.
The BBA’s assessments
of building systems or
MMC, for example, focus
on the demands of UK
building regulations and
also pick up any nonstatutory requirements,
such as those of the
NHBC. There are Agrément
Certificates for building
systems which include
steel and timber framed,
structural insulated
panel systems, insulated
concrete formwork and
composite structures.
Meanwhile, the
Buildoffsite Property
Assurance Scheme
(BOPAS) has been
developed by Lloyd’s
Register, Building
Life Plans (BLP), The
Royal Institution of
Chartered Surveyors
(RICS) and Buildoffsite,
in consultation with the
Council of Mortgage
Lenders and the Building
Societies Association. The
scheme was developed
following consultations
with the main UK
lenders to address their
perceived risks in lending
against non-traditional
construction systems. BOPAS comprises a
rigorous durability and
maintenance assessment
and process accreditation,
supported by a webenabled database which
gives access to details
of assessed building
systems, registered
sites and individual
properties which have
been warranted under
the scheme. The data
base not only holds
information relating
to first sales after
construction but will be
accessible for the life of
a property, allowing all
subsequent sales to be
similarly checked against
the database (www.bopas.
org). Terry Mundy, UK
Business Development
Manager, Lloyds
Register EMEA, stated
that the BOPAS
process, supported by
the insurance based
10-12 year warranty,
was acknowledged
by the principal
lenders as mitigating
their perceived risks
associated with lending
against non-traditional
construction systems.
And the transparency
afforded by the BOPAS
web-based data base
provided valuers with the
confidence to accurately
value non-traditional
properties listed on the
data base and supported
second hand values
tracking the market mean.
A number of those
involved in factory-made
housing say that finance
has not been a issue.
Mar City, a housebuilder
specialising in modular
offsite construction
techniques, told
us: “Mortgages are fine;
people have moved in on
a number of our sites and
have building insurance
and NHBC warranty. Our
homes have sold well.”
PRP Chairman Andy
Von Bradsky, architect
of the Oval Quarter in
Lewisham,one of our case
studies, said: “The new
houses have been very
well received by returning
residents and on the
open market. There have
been no bad perceptions
about offsite production
as they are traditional in
appearance.”
Getting insurance
A potential drawback of
using modern methods
of construction is the
perception that insurers
can be reluctant to
offer cover, particularly
for timber frame
construction. However, the
NHBC’s Graham Perrior,
says, “There should not
be a problem getting
buildings and contents
insurance with the proviso
they are designed and
built properly. Timber
frame housing should
present no more fire
risk than masonry
construction. Arguably,
there could be more risk
during construction in
that the timber can be
exposed, but significant
work has been carried
out over recent years
to reduce this risk and
once completed it is fully
protected.”
Extending the property
A concern flagged up
by some homeowners
is whether homes built
offsite with prefabricated
methods provide the
same degree of flexibility
to extend as those built
using traditional systems.
Volumetric systems can
be more difficult in terms
of flexibility to extend,
but panellised systems
should be no more
difficult than conventional
construction, says
Fusion Building Systems’
Business Development
Manager Stewart Hackney Expert Opinion
Rory Bergin
16
More Homes Through Manufacture
A Housing Forum Working Group Report
EXPERT OPINION:
WHY WOULDN’T
YOU BUY A
FACTORY
BUILT HOME?
MANUFACTURED HOUSES WILL ALLOW
CONSUMERS TO CUSTOMISE THEIR
HOUSES, SAYS ARCHITECT RORY BERGIN
here are many good reasons why new modern
homes should be made in a factory. There are
no good reasons why they shouldn’t. Practically
everything else we use in our lives comes from
a factory and we are very happy with them. We
expect our cars, TVs, computers and phones to be
mass-produced, and would be very surprised to
find that they weren’t. In fact we wouldn’t buy them
if we found that they were hand-made by a group of
people brought together in a muddy field and given
instructions in a language not their own, and chosen
because they provided the lowest price, or just
happened to be available that day. That’s how a lot of
housing is currently constructed in the UK.
Manufactured homes are more likely to meet
the stringent quality standards demanded by
regulations for new homes because it’s much easier
to check quality when the product is being made in
a warm building, out of the wind and rain. Workers
of all ages and backgrounds can be employed in
a factory because they are not expected to carry
heavy loads up ladders, or withstand the cold. So
the workforce can be from a wider demographic and
different backgrounds. In the current economic conditions this factor is
lowering the cost of building homes in a factory as
wages for fully employed people are stable. The selfemployed sub-contractors who do much of the work
on traditional building sites are raising their wages
as much as possible because they can. In the rush
to build homes, there is a shortage of labour such
as bricklayers and carpenters, so the ones that are
available can charge more for their skills. Factories are less exposed to this wage inflation
because their workers are permanently employed
and therefore can’t demand increases in their
wages at short notice. Factory owners tell me that
last year, their homes were more expensive to build
than traditional buildings, but could be built more
quickly. This year they can be built for the same
price, but more quickly, and next year they will be
cheaper to build, and more quickly.
There is a further promise of factory production
which is the expectation that someday we will
be able to order our home online and change the
design to suit ourselves. If this sounds far-fetched,
they have been doing this in Japan for decades.
Companies with familiar names like Toyota have
constructed tens of thousands of such homes
for their customers, most of which have been
customised to some degree.
Factories with a high degree of automation can
cope with a change in design easily, provided that
the robot can be given the correct template to use; it
doesn’t care if it does the same job ten times a day,
or ten different jobs. The key element is that the robot is given a
template to work from. Customisation does not
mean that the customer can have what they want
in every case; it means they can choose from a
wide range of features, which ensures that no
two houses are ever the same. It only takes nine
variants in a house design to produce over 300,000
different homes, so customers can be satisfied
that they have a unique product and the factory can
continue to produce a unique design from relatively
standardised components.
There is a reason why the difference in quality
between a factory-made home and a traditionally
built home is not obvious to the average housebuyer
or renter. No-one tells them, and the quality
difference is not reflected in the sales price. We
have the ridiculous situation where the location and
number of bedrooms in a property sets the value,
and the quality of the finished home counts for
17
nothing. If a housebuilder does a very good job of building a
traditional home or a bad job, it makes no difference
to the price. If the home is hard to heat or very
efficient, it may be interesting to the purchaser,
but it makes no difference to the price. If the three
bedrooms of one property are bigger than the three
bedrooms of the other, it makes no difference to
the price. In a market like this it is very difficult for
a housebuilder to concentrate on a quality product,
since it makes no difference to his profits. We are trying to change this by introducing a way
that purchasers and renters can see the difference
in the quality of their new home. By creating a
Home Performance Labelling tool, The Housing
Forum is enabling people to rank the potential
purchases in order of size, if that’s what they care
about, or energy efficiency, price per square metre,
daylight, or maintenance costs. This way of making
a purchasing choice is familiar to anyone who has
bought a car, insurance, phone, electricity or a fridge
in recent years. We think it’s time that such a tool
was available to the housing market. By helping people to make their choices based
on quantitative information as well as qualitative
information we expect to drive up the quality of
new homes in the same way that comparison
shopping has driven the market in electronic goods.
The product of tomorrow would be better than the
product of today and offered at the same price. This
is how markets should work. There should be room
for low quality products and high quality products,
at different price points, but the housing market
currently values both products in the same way,
leaving no room for quality. Because price is also set
by location the current pricing system keeps the
housing quality low in poor areas and reduces the
likelihood of regeneration. Finally, in order to deliver anything like the number
of homes we need, the housing industry in the UK
must double in size. Output is currently about half
of what we need to sustain the market. This growth
won’t be achieved by adding more workers from
abroad, working in muddy fields at low productivity
levels. It will be achieved if we create a functioning
offsite manufacturing sector, distributed across the
UK, using a well-organised workforce, operating in a
market where higher quality products get the sales
prices that they deserve.
Rory Bergin is a Partner at HTA Design LLP,
which is a member of The Housing Forum
The Hanham Hall
development in
Gloucestershire
designed by HTA
18
Living in a factory
built home
More Homes Through Manufacture
A Housing Forum Working Group Report
LIVING IN A
FACTORY
BUILT HOME
ATTRACTIVE PROPERTIES WITH LOWER ENERGY
BILLS ARE SOME OF THE BENEFITS OF
LIVING IN A FACTORY BUILT HOME, SAY RESIDENTS
PHOTOGRAPHY: ED TYLER
Natasha Devlin
pictured in her new
Passivhaus home in
Coventry
19
20
Living in a factory
built home
“Thanks to
the home
being so well
insulated and
having the
air filtration
system, my
eldest no
longer has
asthma.”
Key building
details:
Building type:
Passivhaus
constructed using
factory-built,
timber frame
panels by Beattie
Passive
Number of homes
in scheme: two
Client: Orbit Group
Development
time: 30 weeks.
Roughly the same
time as would take
for a traditionally
built home
Development
cost: £1,430/m2
for a home built
to the German
Passivhaus
standard. Usual
cost for such a
property is £1,800/
m2, although Orbit
had hoped to do
it for £1,100/m2. A
home built to Code
for Sustainable
Homes level three
would cost £1,000/
m2
Date of
completion:
October 2013
Who lives here:
Resident:
Natasha Devlin,
partner and two
daughters aged 12
and 7
Type of tenure:
social rent of £128
a week
Lived there since:
November 2013
Number of
bedrooms:
three
Occupation:
housewife
More Homes Through Manufacture
A Housing Forum Working Group Report
Natasha Devlin,
John Rous Avenue
Coventry
“When we found we had been successful
in bidding for a house with Orbit, we drove
round to have a look immediately,” says
Natasha Devlin. “I was jumping up and
down in the street when I saw the place.
My first impression was that it is a lovely
property on a great size plot. I was very
happy.”
Ms Devlin was unaware at first that the
house was one of two built by housing
association Orbit Group as part of a
pilot project to explore the use of offsite
manufacturing techniques to construct
homes built to the highly insulated
German Passivhaus standard.
“When I found out it is a Passivhaus,
I felt absolutely brilliant,” she says. “My
children have asthma and we had been
living in an old private rented property
in Coventry that was much colder and
draughty. As a result we had the heating
on almost the whole time and this was
terrible for the girls as it dried the air out
and really affected their asthma.
“Now, thanks to the home being so well
insulated and having the air filtration
system, my eldest is no longer classed as
suffering from asthma and the youngest
is far better too. They both used to suffer
from eczema and that has gone right
down as well,” Ms Devlin adds.
The family’s cost of living has also
dropped substantially. Rent has fallen
from £650 a month in their previous
private rented home to £512. Ms Devlin
says she was spending £40-£60 a week
on electricity and gas, but that this has
now fallen to £150 a month at most.
John Barnham, Head of Sustainable
Investment at Orbit Group, says that
although Orbit is pleased with the
scheme, it has not yet built any further
projects using off-site manufacturing
techniques in its 1,000-home a year
development programme. This is because
it is conducting a review to see what is
a realistic cost for an OSM development
before it commits to further schemes.
Mr Barnham adds that, while
maintenance issues to date have been
no different to those he would expect
on a traditionally built project, there has
been a “real learning curve for staff and
tenants over the use of the mechanical
ventilation kit and generally ensuring the
air-tight membrane of the home is not
punctured by drilling holes for pictures or
to install Sky TV.”
He says Orbit has provided a junction
box for satellite or cable TV that avoids
the need to drill holes and that residents
are informed of this.
Ms Devlin says she would definitely
recommend the home to her friends.
“They are all very envious of the quality of
where I live and have all commented on it.
We’re really happy here and would give it
10 out of 10.”
21
Neil Crowther,
Shepherdess Walk
Islington, North London
“We used to live nearby in private rented
accommodation in Hackney and were first
attracted to living here by the fact we had
some friends who have lived locally since
2002 and they love it,” says Neil Crowther, a
resident of the award-winning Shepherdess
Walk development since August 2006.
The fact that the development – the first
of its kind in the UK and built by Peabody
owing to frustration at the length of time
and cost of traditional methods – is made
from factory-built modules stacked on top
of each other was simply not an issue for Mr
Crowther and his partner. “When we were
thinking about moving here, we liked the fact
it is an attractive building – especially the
balconies, the wood cladding and the lovely
external courtyard. We also liked the fact
that Shepherdess Walk is run by a housing
association, not a private landlord,” he says.
As a long time resident of the east
London borough, Mr Crowther also relishes
the fact that, despite its location, the
property – also more popularly known
as Murray Grove – is cheaper than
others nearby, yet provides generous
accommodation.
“The location is great for us in central
London, five minutes’ walk from Shoreditch
and Clerkenwell. Yet it is surprisingly
peaceful. The flat is spacious and bright and
lets in a huge amount of light.”
Mr Crowther adds that, although his home
has no gas central heating, it warms up
quickly when needed and fuel bills are low
as a result. He does express some concerns
about the quality of the insulation on the
external walls, however, saying the relevant
rooms can feel noticeably colder than others.
This may reflect a concern identified by
Peabody in the build process that, although
the 74 modules were factory-built in 12
weeks and erected on site in 10 days, much
of the remaining build time was taken
up by protracted efforts to satisfactorily
clad Shepherdess Walk and construct the
balconies.
Although generally very happy with the
internal finish of his home, Mr Crowther
suggests the 16-year-old building is
experiencing some wear and tear and that
fixtures and fittings such as curtain rails are
not as easy to replace as might be the case
for a more traditionally built home.
For Nick Hart, a neighbourhood
manager at Peabody with responsibility for
Shepherdess Walk, the block is a “joy” to
maintain. “It simply does not suffer from
the noise and other complaints that are
common in others,” he says. “I expected it
might have noise transmission problems
due to its design, but that simply hasn’t
been the case.”
Mr Crowther says he would live in a
modular home in future, but that, at present,
he and his family are looking to move
somewhere bigger as this isn’t an option at
Shepherdess Walk. He adds: “It works really
well for young people starting out and for us
it was ideal.”
Key building
details:
Building type:
factory-built
modules by
manufacturer
Yorkon
Number of homes
in scheme: 16 onebedroom flats and 14
two-bedroom flats
Client: Peabody
Development
time: 44 weeks
(including 17-week
delay due to
external works
over-running),
versus 62 weeks
for similar
development at
nearby Dalston
Lane using
traditional
techniques
Development
cost: £2.9 million
and £77,800 per
home, versus
£2.7 million and
£76,200 per home
on Dalston Lane
Date of
completion:
November 1999
Who lives here:
Resident:
Neil Crowther,
partner and oneyear-old daughter
Type of tenure:
keyworker rent
Lived there since:
August 2006
Number of
bedrooms: two
Occupation:
public policy
consultant, based
at home
“When we were
thinking about
moving here,
we liked the fact it is
an attractive building.”
22
Living in a factory
built home
More Homes Through Manufacture
A Housing Forum Working Group Report
Peter Webb
Beechdale Estate
Walsall
“We were living nearby in private
rented accommodation and paying
an astronomical rent of £700 a month
before moving here,” says Peter Webb,
who now rents a brand new, three
bedroom detached home in Walsall from
Accord Group.
“The fact it is a factory-built house was
not a factor in our decision to come here
as we didn’t know when we applied for
a home. When we were offered a home
and when we did find out it was a timber
property, we were initially very worried
– it was effectively a wooden shed,’ he
says.
Peter and his family had never
previously lived in a home built using
modern methods of construction and
were concerned about how robust the
property would be. However, he says:
“When we saw the house we instantly
took a liking to it. Once you go inside,
you cannot tell they are wooden houses
– you just can’t. The rooms are more
than big enough and the finish is lovely.
Our friends come round and say ‘it’s all
wood’, but I say ‘come inside’ and people
are really impressed.”
Another aspect that has pleasantly
surprised Peter is the difference in
his energy bills compared to previous
homes. “It is amazing how much lower
they are.” Peter and his family used to
spend around £360 a month on gas,
water and electricity. Now they spend
£80 a month, quarter of their previous
energy expenditure.
This is music to the ears of Alan Yates,
Director of Regeneration at Accord
Group: “It’s incredible really, the savings
our residents can make and it is great
for everyone – especially those on low
incomes.”
Key building
details:
Building type:
Factory-built,
‘closed’ timber
panels by Accord’s
LoCal Homes
factory
Number of homes
in scheme: 40
Client: Accord
Group
Development
cost:
Just under £1,000/
m2 for a Code
for Sustainable
Homes level four
home, a 20 per
cent saving on
cost for a home
built to Code
for Sustainable
Homes level three
using traditional
methods
Date of
completion:
January 2015
Who lives here:
Peter Webb, wife
and two adult
children
Type of tenure:
Affordable rent of
£115 a week
Lived there since:
January 2015
Number of
bedrooms: three
Occupation:
Motorway
maintenance
supervisor
Mr Yates says Accord has been
building homes from the LoCal Homes
factory it owns in Walsall for four years
and half its 300 new homes a year are
supplied by the factory’s 20 locally based
staff. The aim is to increase this to 200
a year and to boost production to 400
homes annually overall by working with
new clients such as Rooftop Housing
Group and Stafford and Rural Homes.
He says Accord runs the factory –
the first of its kind by a UK housing
association – as it creates jobs in its
communities and costs a fifth less than
traditional building techniques for a
better quality home.
“To maintain, there is really no
difference to a traditionally built home,”
Mr Yates says. “We go for a fabric-first
approach with loads of insulation to
ensure energy bills are low and there is
no need for lots of other expensive kit.”
Accord Group has sold 70-80 LoCal
Homes on the open market too, with
plans to do more.
“Overall we are loving our home,” says
Mr Webb. “I work nights and so have
to sleep during the day. Despite the
fact some homes are still being built
nearby, you can’t hear a thing. I give this
home nine out of 10 and would definitely
recommend it to anyone.”
”Peter’s energy bills
are now £80 a month.
He used to spend
£360 a month.”
23
Expert Opinion
Jim Martin
24
More Homes Through Manufacture
A Housing Forum Working Group Report
EXPERT OPINION:
FROM FEEDING
THE CAT TO
ORDERING FOOD
JIM MARTIN EXPLAINS WHY
HOMES ARE SET TO GET SMARTER
e are at the beginning of a revolution in the way we
live in our homes. The internet, mobile devices and
greater connectivity will give us the ability to live and
manage our homes in an entirely different fashion.
In 1975, only a tiny percentage of homes in the UK
had gas central heating; 40 years later almost all UK
homes are centrally heated, mainly by gas. Notably,
central heating has changed the way we live and
manage our homes. In the same way, smart home
technologies provide the opportunity for a similar
revolution. Within the next 40 years, a large proportion
of homes in the UK will have ‘smart’ home elements.
The definition of a smart home is generally agreed
to be: “A dwelling incorporating a communications
network that connects the key electrical appliances
and services, and allows them to be remotely
controlled, monitored or accessed.” Remotely in this
context can mean both within the dwelling and from
outside the dwelling. There are three things a home
needs to make it smart: Internal network – wire, cable, wireless
Intelligent control – gateway to manage the systems
Home automation – links between products, services
and external systems
A key advantage of using smart home technology
is that homeowners are given more control over
their appliances and devices. For example, a smart
home boiler can tell you when it needs servicing or is
running inefficiently. The refrigerator may also be able
to list its contents and order food.
Using smart home technologies, devices can be
connected to each other, which allows the passing
of information to and from devices. A quick glance
at their smartphones or tablets will provide
the following information, when smart home
homeowners are away: Did I turn the cooker off?
Did I set the home alarm system? Are the kids
doing their homework or watching television?
Smart home technology is also known for home
security features. The lights can be turned on and
off to prevent burglaries and home intrusions –
and in future the home will be programmed to
water the garden or feed the cat.
While it is exciting to think about this technical
revolution, which is changing the way we live
through greater connectivity, there are various
practical applications of smart home technologies,
not only home entertainment, clever security
and energy management. As the population
grows older, more home care will be required for
many people. Remote monitoring and control
are huge advantages in allowing elderly people
to stay in their homes whilst using occupant
monitoring, movement monitoring to detect falls
and medication reminders to name but a few.
A similar list could apply to infant monitoring or
people with disabilities. Smart Homes technologies
can be retrofitted, they can be incorporated into a
traditional build process but it is as a component
in an OSM process that smart home technologies
come into their own. In the same way a purchaser
will select from a list of options when buying a
car, a home purchaser will select from a range of
smart options to be incorporated within the factory
process.
In fact, the application of smart home technology
is limitless.
Jim Martin is Senior Partner, Martin Arnold and
Chair of The Housing Forum’s Working Group,
Smarter Supply: Smarter Resources
25
26
Case studies
Transforming Construction
More Homes Through Manufacture
A Housing Forum Working Group Report
TRANSFORMING
CONSTRUCTION
HOUSING SCHEMES AROUND THE UK ARE BEING BUILT
MORE QUICKLY USING OFFSITE PREFABRICATION
TECHNIQUES AS ILLUSTRATED BY THESE 12 CASE STUDIES
Offsite prefabrication was used
extensively at the
Olympic Way
development
in Wembley
27
28
Case studies
Transforming Construction
More Homes Through Manufacture
A Housing Forum Working Group Report
Case study 1
Showell Court,
Wolverhampton
Contributed by Paul O’Driscoll
Wates Living Space
[email protected]
Name of project:
Showell Court
Town or city:
Wolverhampton
Brief description:
64 apartment extracare home
with communal facilities
including sensory garden.
Total cost: £7.2m
Average cost per unit:
£114,286
Principal partners:
Wates (constructor), Pozzoni
(the architect), DWP (services
engineer) Stewart & Harris
(structural engineer) Hemsec
(the system provider) and
Accord Housing Association
(client).
Completed: October 2009
Length of time to build:
60 weeks (further time
would have been saved but
for tolerance problems with
precast concrete planks)
Estimated time using
traditional methods (from
start on site ): 70 weeks
Briefly describe the
construction method
The offsite method involved
the use of structurally
insulated panels (SIPs) and
precast concrete floor planks
and stairs, externally clad
in traditional brick work and
look-alike copper cladding
with a structural steel
transfer slab with communal
facilities. Erected using
forklift.
Why was this method
chosen?
Due to limited design
available at tender we needed
to delay the start on site to
allow a fully co-ordinated
scheme to be provided
whilst still maintaining the
critical end date for Accord.
Changing from traditional to
SIPs with precast concrete
(PCC) planks allowed more
time at the front end to
complete the design and
Accord’s brief. The use of PCC
planks and SIPs also avoided
the issues of overheating and
excessive cooling plant often
required with standard timber
frame.
Were there any additional/
unusual approvals needed
and what were they?
The SIPs and precast
concrete floor were unusual
and therefore an engineer
was used to ensure that this
composite system worked
structurally. The engineer
worked closely with the
SIPs manufacturer and the
pre-cast plank company on
behalf of Wates to ensure this
innovative structural solution
met current regulations. We
also needed to agree a new
suite of bespoke Robust
Details with Building Control
and NHBC as this was the
first time this system had
been used for residential
developments.
How did costs compare with
traditional methods?
Slightly more expensive
for construction materials,
however the preliminaries
saving covered this extra
cost.
Would you use this method
again? Yes
What are your
reasons?
Speed and ease of build and
because it provides a higher
thermal mass which reduces
overheating.
Other comments on offsite
manufacture for housing
construction?
The offsite components
were a good quality product,
manufactured in a quality
environment. We still suffered
design issues and perhaps if
the use of BIM was employed,
these design/sizing issues
may have been prevented.
29
Case study 2
The Oval
Quarter,Lambeth,
South London
Contributed by Rick Burgess
PRP
Rick.Burgess
@prparchitects.co.uk
Name of project:
Oval Quarter, Lambeth
(formerly Myatts Field
Estate)
Town or city:
Lambeth, South
London
Brief description:
982 new homes in
comprehensive PFI
regeneration of Myatts Field
Estate, Lambeth. The Oval
Quarter consists of 134 houses,
160 maisonettes and 688
apartments, plus a new public
park, community centre and
new district combined heat
and power system Total cost:
£110 million (includes
infrastructure, external works,
community centre)
Principal partners: Lambeth
(client) in joint venture
partnership between
Regenter & Higgins Group.
Higgins Construction (main
contractor)PRP (architect)
Length of time to build:
Phase 1, 485 units in 23 Blocks
completed in 24 months;
Phase 2, 497 units in 11 blocks
commenced
Briefly describe the
construction method
Selected OSM system is
light gauge steel (LGS)
superstructure frame
including prefabricated wall
panels and floor and balcony
cassettes. Why was this method
chosen?
All the known benefits of
OSM, such as reduced
onsite construction period,
improved health and safety,
increased quality, less
waste, and overcoming the
lack of on-site trade skills
so fewer defects. Plus OSM
offers very accurate system
in terms of controlling
geometry and tolerances.
It significantly reduces
foundation loads (and hence
ground works costs). It
avoids differential movement
issues associated with
timber frame. And it achieves
significant acceleration
in superstructure frame
erection relative to traditional
site based methods.
In addition, the integrated
design concept gives early
technical input on design
requirements for OSM
system, thus embedding
accuracy and deliverability
in the planning design. So,
many efficiencies derive from
this rigorous approach.
How did costs compare with
traditional methods?
We are awaiting advice on
cost comparison.
Would you use this method
again? Yes. What are your reasons?
All of the above, plus
additional benefits
realised through working
collaboratively with Metek
using BIM, such as high level
of quality control during
manufacture in factory and
assembly on site; waste
recycling in manufacture
and reduction of on-site
waste; and easier resolution
of spatial ‘clashes’ such as
clashes with hot-rolled steel
elements prior to site .
Any other comments on
offsite manufacture for
housing construction?
The key reasons for
success on this project
are the early decision on
selecting OSM system
during the design stage,
and excellent collaborative
working between the client,
constructor, design team and
system supplier.
30
Case studies
Transforming Construction
Case study 3
Kirklees PFI,
Huddersfield
Contributed by Bev Grey
Wates Living Space,East
[email protected]
More Homes Through Manufacture
A Housing Forum Working Group Report
Name of project:
Kirklees PFI Excellent Homes
for Life
Town or city:
Huddersfield and Dewsbury
Brief description:
The project includes
construction of three extracare housing schemes
containing 140 new homes for
older people and a further 291
one and two bedroom homes
with 35 homes specifically
designed for wheelchair
users over 27 separate sites
throughout the Kirklees area.
Total cost: £69m
Average cost per unit:
£100,000
Completed: March 2014
Principal partners:
Kirklees Council and Regenter
Excellent Homes for Life
Consortium,Wates Living
Space (main contractor),
Watson Batty Architects &
MET Consultancy(designers).
Length of time to build (from
start on site): 2 years, 3 months
Estimated length of time
to build if using traditional
methods (from start on site):
2 years, 9 months
Briefly describe the
construction method
Pre-insulated open panel
timber frame.
Why was this method
chosen?
Greater predictability of
programme delivery, taking
brickwork off the critical path
& reducing labour resource.
How did costs compare with
traditional methods?
Main benefit was the time
saving, which allowed the
client to maximize early rental
income.
Would you use this method
again? Yes.
What are your reasons?
Predictability of time and
reduction of critical labour
resources.
Were there any difficulties
with the method chosen?
Main issue is effect of
inclement weather and
control of moisture content
which leads to requirement to
allow drying out period within
programme
31
Any other comments on
offsite manufacture for
housing construction?
Although not necessarily
a cheaper method of
construction, the use of
timber frame makes for a
more predictable delivery
programme. It contributes
to the simplification and
standardisation of details
to achieve a high standard
construction, allowing both
client and contractor a
greater degree of confidence
from the outset.
Where there any additional/
unusual approvals needed
and what were they?
After the general election in
2010, the government asked
for an additional value for
money exercise as part of the
sign off on PFI schemes. We
were requested to produce a
value for money assessment
for the Housing Minister.
This scheme exceeded the
required standard
and obtained the necessary
sign off.
32
Case studies
Transforming Construction
More Homes Through Manufacture
A Housing Forum Working Group Report
Case study 4
School Mews,
Hastings
Contributed by
Richard Barwick
For Southern Housing Group
[email protected]
Name of project:
School Mews
Town or city:
Hastings
Brief description – house
types & tenure and number
of units
15 new homes, all affordable rent
Total cost:
Part of £60k per plot
competiton, total cost with
abnormals and land: circa
£1.5m
Average cost per unit:
£100k (approx)
Principal partners:
Southern Housing Group
(client); developer SEEDA
Completion: 2008
Length of time to build (from
start on site ): 40 weeks
Estimated length of time
to build if using traditional
methods (from start on site):
30 weeks (against 50
traditional) allowing abnormal
groundworks( unclear)
Briefly describe the
construction method
A mixture of timber frame/
steel frame/ volumetric/
timber finished fully insulated
panels; triple glazed windows;
pre-installed plumbing.
Why was this method
chosen?
One of Design For
Manufacture submission
winners (second tranche)
How did costs compare with
traditional methods?
10 percent higher
Would you use this method
again? Yes
What are your reasons?
A proven German company
with good track record and
high quality system.
Were any difficulties with the
method chosen?
Weberhaus demonstrated
excellent thermal efficiency
and air-tightness resulting
in low carbon footprint
and lower running costs.
Unfortunately, Weberhaus
now appear to focus on the
one-off schemes, no longer
affordable high volume
schemes.
Who are the principal
partners?
Southern Housing Group
and Weberhaus with Radley
House Architects
Any other comments on
offsite manufacture for
housing construction?
An enlightened client, using
a recognised manufacturer
and a good design team with
the relevant experience is the
best way to proceed. There
are challenges, but these can
be overcome.
Were there any additional/
unusual approvals needed
and what were they?
Achieved Building for Life;
Code for Sustainable Homes
(4), Secured by Design,
Housing Quality Indicators
33
Case study 5
Sampson Close,
Coventry
Contributed by Paul O’Driscoll
Wates Living Space
[email protected]
Name of project:
Sampson Close
Town or city: Coventry
Brief description:
Five two and three-bed
terraced houses and 18 twobed apartments built using
the Passivhaus approach
Total cost: £3.5m
Average cost per unit:
£152,000
Principal partners:
Orbit Homes (client), Wates
Living Space (contractor),
Baily Garner (architect),
Stewart & Harris (consulting
engineers)
Length of time to build:
12 months
Is the project complete? Yes
When was it completed?
Apr 11
Estimated length of time
to build if using traditional
methods: 14 months
Were there any additional/
unusual approvals needed
and what were they?
Passivhaus certification to
ensure that all parameters set
by Passivhaus were achieved,
such as extremely low air
leakage of 0.6
Briefly describe the
construction method
Composite panel super
structure (including windows
and services) with 250mm of
cellulose insulation, external
brickwork, render and
thermowood.
Why was this method
chosen?
To ensure that the thermal
qualities and low air leakage
requirements were achieved.
How did costs compare with
traditional methods?
High premium due to this
scheme being an R&D
type project. Not many
manufacturers of specialist
heat and ventilation product
in the UK, if any, at the
time and the frame and
mechanical/ventilation
equipment was sourced from
Europe.
Would you use this method
again?
Method of using
Germanpanel system with
pre-installed Passivhaus
certified windows is a tried
and tested method on the
continent. However, in the UK,
this is expensive and still has
risks attached. In Germany
apartments are larger than
apartments in the UK which
helps with achieving the air
leakage requirements, but
it is more difficult in the UK.
Preference to use traditional
method of construction in the
UK for cost reasons, although
more difficult to achieve
standards.
What are your reasons?
There are various methods
which could be adopted, such
as traditional build, the main
factor being that building
regulations in the UK requires
air leakage at 7 (was 10 at the
time), whereas a Passivhaus
requires 0.6.
Were there any difficulties
with the method chosen?
Method chosen was the
correct method, although
there was not enough
understanding of the design,
which has a huge impact
on the cost to build and the
ability to achieve Passivhaus
certification. Properties
need to be designed larger;
products to cope with air
movement need to be
sourced from the UK; and
robust methods for achieving
air leakage need to be readily
available in the UK.
Any other comments
on offsite manufacture
for housing
construction?
Offsite manufacture allows
the precision required, and
the panel system used on
this scheme was erected
and water/weather tight
within two weeks of being
delivered to site. The frame
and windows were nearly 50
percent of the scheme costs.
34
Case studies
Transforming Construction
More Homes Through Manufacture
A Housing Forum Working Group Report
Case study 6
The Greenhauses,
West London
Contributed by Kingspan Insulation
technical@kingspaninsulation.
co.uk
Name of project:
The Greenhauses, Brook
Green
Town or city: London
Brief description:
Thirty new homes, including
eight for outright private
sale, 13 for shared ownership
and nine for affordable rent.
The site comprises a row of
three-storey terraces (Block
A), two five-storey apartment
buildings (Blocks B & C) and a
further four mews houses with
roof terraces (Block D). Both
Blocks A and B have now been
fully Passivhaus certified.
Total cost: not supplied
Average cost per unit: N/A
Principal partners:
Octavia Housing (client),
Cartwright Pickard
(architects), Durkan
(contractor) and Kingspan
Timber Solutions
Briefly describe the
construction method
On Block A, a breather
membrane was stapled to the
outer face of the Kingspan
TEK Building System (SIPs),
followed by 90 mm thick
Kingspan Kooltherm K12
Framing Board. A 50mm
cavity was then left between
the build-up and the 102.5mm
brickwork facing. Internally an
airtight membrane was taped
to the Kingspan TEK Building
System’s face, followed with
a 25mm service zone and two
15mm layers of plasterboard
lining. The Kingspan TEK
Cladding Panels (SIPs)
installed on Block B were fixed
to the concrete floor slab
using angled cleats. The buildup mirrored those in Block A
with the airtight membrane
sealed to the concrete frame
and soffits with airtight tape.
Why was this method
chosen?
Brick was chosen as the
primary façade material
for the buildings. Given
the tight, urban nature of
the site, minimising the
thickness of the remaining
wall build-ups, whilst still
attaining the required level of
thermal performance, was a
key objective. SIPs ensure a
predictable installation with
minimal on-site waste. The
proprietary jointing system
featured on both Kingspan
TEK products, in combination
with the additional
airtightness detailing on the
project, ensured that air loss
from the blocks is below the
0.6 air changes per hour @ 50
Pa. On average, these homes
are anticipated to make
significant savings on fuel
bills (up to 90 percent in the
case of the certified units).
35
Case study 7
Park Heights,
London
Contributed by Steven Busbey
Wates Living Space
[email protected]
Name of project:
Park Heights (former Waylands
House)
Town or city:
Stockwell, South London
Brief description:
Demolition of an existing
15 storey tower block and
replacement with a 20 storey
residential block, including a café
facility. A total of 159 apartments
consisting of 84 affordable and
75 private sales. External works
include car parking and soft
landscaped areas. Designed to
Code Level 4 & Lifetime Homes.
Total cost: £27.4m
Average cost per unit:
£172,000
Principal partners:
Network Housing Group
(client), Wates Living Space
(main contractor),GCL (frame
contractor), Conisbee(engineer),
Oran Pre-cast (manufacturer)
Completion:
December 2015 Length of time to build (from
start on site ):
100 weeks
Estimated length of time
to build if using traditional
methods (from start on site ):
106 weeks
Briefly describe the
construction method
Offsite manufactured precast
concrete frame elements,
comprised pre-cast
reinforced concrete structural
columns, along with twin-wall
core-walls and lift shafts
were incorporated into a
post-tensioned flat-slab
reinforced concrete frame
to expedite the construction
of the superstructure. The
twin-wall system consists
of two 65mm thick concrete
leafs joined together by
steel, lattice reinforcement
to form a structural panel.
Once the panel is positioned
on site, it is filled with poured
concrete. Why was this method
chosen?
Mainly to expedite the
construction of the reinforced
concrete frame through
reduced Man hours, faster
on-site construction times
and reduced site labour and
materials. It also allowed
for high quality finish and
control.
How did costs compare with
traditional methods?
When assessed holistically
and, whilst also taking into
consideration the reduced
labour, falsework and
programme and prelims
savings, this method was
considered more cost
effective than a traditional
approach. Would you use this method
again?
Yes
What are your reasons?
Because of the benefits
mentioned above
Were there any difficulties
with the method chosen?
No difficulties but it does
require a design input
from the specialist via
the reinforced concrete
frame contractor which
brings with it a need for
good design management/
coordination
Were there any additional/
unusual approvals needed
and what were they?
No unusual approvals. A
review of the manufacturer’s
design and calculations was
undertaken by our structural
engineer and a co-ordination
review exercise was
undertaken by our architect
which would be the standard
approach with any contractor
design package.
36
Case studies
Transforming Construction
More Homes Through Manufacture
A Housing Forum Working Group Report
Case study 8
Riverlight,
Vauxhall, London
Contributed by Leona Eze
Martin Arnold
[email protected]
Name of project: Riverlight
Town or City:
Nine Elms, Vauxhall, London
Brief description:
116 units for shared equity
ownership surrounded by
private gardens and a new
piazza, set on the bank of the
River Thames
Total cost:
£17.5 Million
Average cost per unit:
Not supplied
Expected completion:
September 2016
Principal partners:
St James, Berkeley Group
(contractor), Viridian Housing
(client), EPR Architects
(designer); Bathsystem (
manufacturer) Martin Arnold
(employer’s agent).
Length of time to build (from
start on site ): two years
Estimated length of time
to build if using traditional
methods (from start on site ):
108 weeks
Briefly describe the
construction method
Offsite construction of
bathroom pods were used
for this development and
included fixtures and fittings
and services ready for
connection.
Why was this method
chosen?
Delivering pods that are ‘fit
for purpose’ helped reduce
the construction time,
making the programme more
efficient and reducing our
carbon footprint. The pods
benefited from a high quality
control within the factory
enabled a high quality finish
on the pods.
How did costs compare with
traditional methods?
At present, the development
is still under construction.
Therefore, it is difficult to
assess the cost-efficiency
savings in comparison to
traditional methods.
Would you use this method
again?
This method of modular
construction is gaining
momentum within our
projects.
What are your reasons?
The method offers a range
of advantages. Using offsite
construction and producing
the pods abroad helped
minimise risks and health
& safety issues. Producing
materials in a factory enabled
readily available materials
to be transported to the new
development. Fundamentally,
this method is an effective
modern method of
construction, which produced
a high quality finish.
Were there any difficulties
with the method chosen
No issues have currently
been reported.
Were there any additional/
unusual approvals needed
and what were they?
Using one of the main
products of modern methods
of construction, modules
were selected for this project.
Any other comments on
offsite manufacture for
housing construction?
Adopting modern methods of
construction, we developed
bespoke bathroom pods
to meet our client’s
specification requirements.
The pods were manufactured
ahead of time and shipped
from mainland Europe before
being craned into position
and connected to the
superstructure and services.
The pods will add great value
to this major regeneration
development for the riverside
community to enjoy.
37
Case study 9
Kidwell’s Estate,
Maidenhead
Contributed by Paul Inch
Innovaré Systems
[email protected]
David Fish
Wates Living Space
[email protected]
Name of project:
Kidwell’s Estate
Town or city:
Maidenhead
Brief description:
The mixed tenure scheme
consists of apartment
blocks providing a mix of
one, two, three and four bed
homes and a new communal
space. Works consisted of
the demolition of existing
residential units followed by
the construction of seven
blocks across 3-5 storey
height. In total, 204 units were
constructed over four phases.
Total cost:
£26 million
Average cost per unit:
Not supplied
Principal partners:
Wates Living
Space(contractor), Innovaré
Systems (designer), Innovaré
Systems (manufacturer),One
Housing Group
(client),Reddington(frame
and groundworks),
Clearwall (drylining) and
Entric(electrical),Peter Taylor
Architects (architect) Ramboll
( structural engineer)
Length of time to build (from
start on site):
Works for phase one
commenced in September
2010, with completion
scheduled for June 2015. 57
months
Estimated length of time
to build if using traditional
methods (from start on site ):
6 months longer, 63 months
in total
Briefly describe the
construction method
SIP infill to concrete frame.
Innovaré provided 162 mm
i-SIP panels which could
achieve a low 0.19/W/m²K
u-value. The sub-structure is
a mass fill foundation.
Why was this method
chosen?
i-SIP infill consists of
structural insulated panels
manufactured offsite and
transported to the building
site. As the panels are
prefabricated, infill does
not have to be assembled
by hand. Kidwells Estate
has constrained access in
a number of areas due to
low rise buildings in close
proximity to each other. This
live site also had a number
of noise restrictions due
to residents remaining
on the estate while works
were taking place. A high
performance infill solution
was needed to combat the
increasing costs of energy
faced by residents.
How did costs compare with
traditional methods?
The Wates project team
concluded that the switch to
the i-SIP system made a 10
percent overall programme
gain and a 25 percent
saving of the cost of their
mechanical and electrical
provision. Significant
financial benefits were
delivered, as Innovaré did
not require scaffolding
during their works and also
replaced edge protection as
they completed each floor by
virtue of including a timber
barrier to all apertures.
Would you use this method
again?
Yes.
What are your reasons?
It potentially reduces
scaffolding costs. Scaffold
periods are reduced by using
SIPs. The infill is quick to
install and is high performing
thermally. It integrates
well with pre and follow on
trades, removes the risk and
hassle from the construction
site.
38
Case studies
Transforming Construction
Case study 10
Olympic Way,
London
Contributed by Rory Bergin
HTA Design LLP
[email protected]
Name of project:
Olympic Way
Town or city:
Wembley, London
Brief description:
As one of the tallest modular
buildings in London, the Shubette
House re-development sits at a
prominent junction adjacent to
Olympic Way, the main pedestrian
route connecting Wembley
Station and the stadium. With
158 new homes and a 237
room hotel (with commercial
and leisure uses, associated
parking, landscaping and play)
the project delivers a new mixed
use scheme of the highest
quality, delivering much needed
housing (private, affordable and
rent) and amenity provision
to the area. The buildings
were designed for offsite
manufacture using the Vision
Modular System - a volumetric
solution delivering advantages
in speed of construction and
reductions in defects while
offering the flexibility to deliver
the varied forms and tower that
are incorporated in the design.
The tenure mix is: 83 percent
private, 17 percent affordable, 7.5
percent social rent, 9.5 percent
intermediate.
Total cost: £44 million
Average cost per unit:
not supplied
Principal partners:
Donban Construction
(contractor), Network Housing
Group, Pinnacle, Novotel,
Residor by Radisson HTA
Design LLP (architect).
Completed: 2013
Length of time to build (from
start on site ):
January 2011 – November 2012
(onsite for 1.5 years) External
delay of 6 months.
Estimated length of time
to build if using traditional
methods (from start on site):
2.5 years
More Homes Through Manufacture
A Housing Forum Working Group Report
39
Briefly describe the
construction method
Volumetric construction, steel
frame modules, slip-form
concrete for cores, rainscreen
cladding, concrete podium
over parking. The entire
scheme has been designed
to be constructed from
steel volumetric pods. We
believe it to be the tallest
volumetric residential
tower in Europe. Through
volumetric construction the
scheme aimed to improve build
quality, reduce construction
waste and speed up the
construction process. The
tower balconies were
constructed as part of the
modules and used as supports
for the façade works, removing
the need to scaffold the
building.
Why was this method
chosen?
The system is the contractor’s
preferred construction
method.
How did costs compare with
traditional methods?
Similar costs but shorter
construction period.
Were there any additional/
unusual approvals needed?
No.
Would you use this method again?
Yes, we are working on three more
projects with the contractor.
What are your reasons?
Quality of the build, speed of
construction, repeat business.
Were there any difficulties with
the method chosen?
Design decisions must be made
on time to enable the factory to
start production of the modules.
Stacked structures and services
are needed in the design.
40
Case studies
Transforming Construction
More Homes Through Manufacture
A Housing Forum Working Group Report
Case study 11
Enfield Small
Sites, North
London
Contributed by Iain Stevens
Airey Miller Partnership LLP
[email protected]
Name of project:
Enfield Small Sites
Town or city:
Enfield, North London
Brief description:
Seven schemes - Parsonage
Lane, Jasper Close, Forty Hill,
St George Road, Lavender Hill,
Tudor Crescent, Holtwhites
Hill - comprising 94 dwellings.
Mix of houses and apartments
for market rent, social rent and
shared ownership.
Total cost: Approximately £15m
Average cost per unit: £160k
Principal partners:
London Borough of Enfield
(client) Kier Project Investment
(main contractor), Climate
Energy Homes (principal
contractor), Airey Miller (project
manager / emplyer’s agent),
HTA Design LLP(planning
architect) BDG Design
(executive architect)
Length of time to build:
18 months (completion in
December 2015)
Briefly describe the
construction method
Offsite manufacture has
been used, in the form of
the EcoTech Timber Frame
system supplied by Climate
Energy Homes, to provide
high quality, sustainable
housing on time and in
budget. All dwellings were
constructed to Code for
Sustainable Homes Level 4;
however, the system lends
itself to achieving all code
levels, zero carbon and
passive houses.
How did costs compare with
traditional methods?
Costs were comparable to
traditional construction and
the EcoTech System provides
long-term benefits in terms
of whole life costs and
running costs for energy bills.
Why was this method
chosen?
The EcoTech system was
chosen to achieve high
sustainability and quality
levels whilst achieving a
fast delivery programme
to compliment the PRS
approach.
What are your reasons?
To achieve high quality and
swift project delivery and
allow the client to use the
private rental market income
to generate funds for future
development in the borough.
Would you use this method
again?
Yes, and the Enfield Small
Sites project is currently
being extended to
provide an additional four
schemes.
Were there any difficulties
with the method chosen?
There were design challenges
with tailoring the traditionally
designed scheme approved
by planning with the EcoTech
system but this is being
successfully overcome.
41
Case study 12
Hanham Hall,
Gloucestershire
Contributed by Paul Newman
Kingspan Timber Solutions
[email protected]
Name of project:
Hanham Hall
Town or city:
South Gloucestershire
Brief description:
Range of one to five
bedroomed properties: in all,
185 properties.
Total cost:
not supplied
Average cost per unit:
not supplied
Principal partners:
Barratt Development
(client), HTA Design
LLP (architect), Barratt
Homes, Sovereign Housing
Association, Kingspan Timber
Solutions
Length of time to build:
About three years
Were there any additional/
unusual approvals needed
and what were they?
Zero carbon development
needed to meet demanding
requirements of ‘Carbon
Challenge’.
Briefly describe the
construction method
Structural insulated panels
(SIPs). In a typical external
wall construction, a vapour
barrier was stapled to the
external face of the Kingspan
TEK Building System panels
followed by timber cladding
fixed on battens. Then,
25mm-thick Kingspan
Insulation Thermawall TW55
was installed internally,
helping to further reduce
both heat loss and thermal
bridging, followed with a
service cavity and a layer of
plasterboard. This internal
build-up was also used for
the roofs.
Why was this method
chosen?
High performance
characteristics of Kingspan
TEK Building System and
established track record
in assisting projects
reach the top standards in
building performance. The
constructions also achieved
outstanding thermal
performance, with a typical
roof and wall U-value of 0.11
Wm2/K, whilst the Kingspan
TEK Building System’s unique
jointing system helped
maintain air leakage rates
below the target maximum of
1.5 m3/m2/hr @50 Pa.
Expert Opinion
Andy Von Bradsky
42
More Homes Through Manufacture
A Housing Forum Working Group Report
EXPERT OPINION:
THE
DIGITAL
REVOLUTION
ANDY VON BRADSKY ON
INTEGRATING DIGITAL TECHNOLOGY
AND OFFSITE PREFABRICATION
1
Metek steel frame
federated with
architectural BIM
2
3
Design clashes
identified prior
to construction,
reducing risk
Architectural
model includes
and coordinates
service intake and
slab setting out
onstruction in the UK is increasingly using
digital technology to speed design and improve
efficiencies and this is beginning to be taken up in
modern housing construction.
So-called Building Information Modelling (BIM) can
be thought of as creating a virtual prototype. It allows
any aspect of a design’s performance to be simulated
and assessed before it is built – helping to understand
the design more completely and much earlier and
so reduce expensive risks later in the construction
process.. The information generated in this digital model
can provide a blueprint for a factory to manufacture
components based on the design a process known as
design for manufacture and assembly (DfMA).
Using DfMA has benefits for customers in that
they can visualise what the home will look like, and
it also makes it easier to customise the design
to reflect consumer choices. The BIM data is
stored and can be accessed digitally for whole life
management and maintenance regimes. It also benefits the contractor because
BIM-generated information is transferred to
manufacturing software, enabling the production
of frame construction drawings in remote factories,
which is then used for the direct manufacture of
components. Modelling off-site manufactured
elements can halve the labour needed when linked
to Computer Aided Manufacture operated robotics.
BIM was used extensively in the prefabrication of
components at the Oval Quarter in Lambeth, where
PRP was the architect (see page 29). We worked
closely with Metek which manufactured the offsite
43
4
5
Exact coordination between
OSM steel frame
and opening in
external wall to
brick dimensions
Environmental
performance of
external building
fabric established early in
design stage with
confidence using
architectural
model content as
basis for analysis
6
7
Availability of
3D views within
construction
documentation
improves communication of the detail
design intent during
procurement and
construction
Using DSfMA
has benefits for
customers in that
they can visualise
what the home
will look like
Integrated modelling process
and collaborative
approach meant
team could
react quickly to
changes
steel framed components as shown above.
Using BIM the fabricator was able to resolve
spatial ‘clashes’ prior to site. The key to success
was collaboration and integration of the supply
chain team early in the design process.
The first two-storey units were built in seven
days as it was critical that occupants could move in
quickly. Zone specific colour-coded sections and BIM
coordinated just-in-time delivery made this possible.
Offsite manufacture and the digital advancement
taking place in the construction industry presents
an exciting time for house building, and one that
should drive benefit for consumers too.
Andy von Bradsky is Chairman of PRP
a member of The Housing Forum
44
Concluding Remarks
More Homes Through Manufacture
A Housing Forum Working Group Report
Concluding
remarks
Jim Martin
Chair of the
Housing
Forum’s Working
Group, Smarter
Supply: Smarter
Resources
Jim Martin, Chair of The Housing Forum’s Working
Group, Smarter Supply: Smarter Resources,
weighs up the evidence for offsite manufacture in
housebuilding.
This report demonstrates that the case for
offsite manufacture (OSM) is compelling. As
we’ve seen from the case studies, prefabricating
homes in factory conditions delivers numerous
advantages.
— Higher quality of building, being assembled in
controlled, benign conditions, from standardising
process and factory testing.
— Greater certainty of programme because of
simplified site processes and works becoming
less weather dependent.
— Improved energy performance through enhanced
specification and controlled, factory processes
which allows much more accurate jointing and
testing of components, to reduce air leakage,
increase insulation and seal airtight components.
— Safer working conditions. Working in a controlled
environment can reduce accidents and improves
safety.
The use of pre-assembled components has been
increasing in many sectors of the construction
industry over the years and it is almost impossible
to build anything without a high proportion of preassembled components within the structure.
New commercial buildings, hotels, education
buildings and health service buildings are all
exhibiting a very high proportion of OSM as
standard: curtain walling, services pods, and
classroom extensions. Existing companies such as
Laing O’Rourke are making major investments in
the OSM process.
The cost of OSM is coming down because
there is now a steady flow of work into the
manufacturing facilities at volumes that make the
process viable. As production runs increase with
volume, the comparative cost should reduce. It is
45
Mar City Homes
specialises in
modular construction to build
homes shown
in these phorographs
also possible to locate the manufacturing facilities
in lower economies, which improves regional
development and reduce overall labour costs.
OSM will reduce preliminaries costs by shortening
project duration.
OSM can offer the standardisation required for
the economies of scale but now OSM can also offer
increased flexibility and customisation by the use
of computer modelling, BIM and greater customer
engagement – in the same way the car industry
does. Because the OSM product is much more
predictable in its construction and performance, it
will allow much more accurate Home Performance
Labelling. This will give purchasers a much greater
level of energy and running cost information when
they buy a new property.
Long term cost reduction can be achieved
through OSM. Labour is always a very significant
component part of the overall cost of a building.
OSM factory-based work can achieve three times
the productivity of site labour, thereby potentially
reducing the labour cost.
Strangely, it is the residential sector that has
been the slowest to embrace OSM, but this is
likely to change. If we, as a nation, are to build
the numbers of homes we need over the next 20
years, we will need to use every means available.
The combined residential development industry
currently has a capacity of about 140,000 homes
per year. We need to develop 200,000 homes
per year, as a minimum, and we will need the
additional homes that can be developed using
OSM in order to make up that shortfall.
There will be hurdles, challenges and problems
to solve ahead but unless we in the residential
development industry begin to embrace OMS
we will not move forward significantly on the
quality of our product, we will not move forward
significantly in terms of energy performance and
perhaps most importantly, we will fall short of the
national target for homes.
46
Credits
More Homes Through Manufacture
A Housing Forum Working Group Report
Credits
The Housing Forum is indebted
to the many people who
contributed to the content,
writing and production of this
publication.
Working Group Chair:
Jim Martin,
Senior Partner, Martin Arnold
Editor and production:
Denise Chevin
Design: Mark Bergin
Contributors and
commentators: Rory Bergin,
Partner, Sustainable Futures,
HTA Design LLP, Andy Von
Bradsky Chairman PRP, Stewart
Hackney, Business Development
Manager, Fusion Building
Systems, James Lidgate,
Head of Residential, Legal &
General, Graham Perrior, Head of
Standards and Technical NHBC,
Terry Mundy UK Business
Development Manager, Lloyds
Register EMEA (for BOPAS ),
Peabody, Orbit and Accord and
Mar City
With thanks to: all case study
contributors and special thanks
for resident case studies to
Natasha Devlin, Peter Webb,
Neil Crowther. Interviews by
Stuart Macdonald, See-Media,
Photography by Ed Tyler.
This report has been developed
by our Smarter Supply:
Smarter Resources Working
Group members:
Tim Attwood,
Director, Conisbee
Steve Bannister,
Procurement Manager, Wates
Living Space
Euan Barr,
Head of New Business, Watford
Community Housing Trust
Richard Barwick,
Interim Construction Project
Manager, The Hyde Group
Tony Battle,
Joint Managing Director, Kind & Co
Rory Bergin,
Partner, Sustainable Futures,
HTA Design LLP
Sally Binns,
Commercial Product Manager,
Marshalls
Graham Brown,
Director (Bouygues UK) and
Board Member South East LEP,
Bouygues UK Housing
Rick Burgess,
Partner - Technical & BIM, PRP
Bobby Chakravarthy,
Associate Partner, Arcus
Andrew Cleaver,
Regional Development Manager,
AkzoNobel
Steve Coleman,
Director, Takeparts
Garfield Coombs,
Business Unit Director – Homes,
Osborne
William Cornall,
Director of Development &
Assets, asra
Darren Eccleston,
Pre-Construction Director,
Wates Living Space
Leona Eze ,
Graduate Building Surveyor,
Martin Arnold ( with thanks for
case study support)
Cody Gaynor,
Managing Director, Space Craft
Architects
Stewart Hackney,
Business Development Manager,
Fusion Building Systems
Adrian Heys,
Head of Development , Town and
Country Housing Association
Roger Holdsworth,
Partner, Pollard Thomas
Edwards Architects
Karen Jones,
UK Housing Building Manager,
Kingspan Insulation
Steve Kane,
Deputy Managing Director, Hill
Charlie Lacy-Scott,
Senior Sales & Marketing
Manager, Willmott Dixon
Gary Lawrence,
Senior Project Manager, Silver
Simon Major,
Commercial Projects Manager ,
AkzoNobel
Alistair McLeod,
Director, Waterstons
James McMillan,
Assistant Development Director,
Great Places
Jon Milburn,
Development Director, Guinness
South
Paul Murtagh,
Director of Property, North
Hertfordshire Homes
Alex O’Keeffe,
Project Manager, Home Group
Sandy Pahl,
Construction Project Manager,
The Hyde Group
Dave Poulter,
Partnership Housing Projects
Director, Wates Living Space