Construction Quality
Reviews
House-Building Standards
Construction Quality Reviews (CQRs)
1
In advance
2 Site Discussion
6 CQR Workshop /
Follow-up
2
3 Site review
5 Distribution & follow-up
4
Site Manager
meeting
Revised Build Stages
1. FOUNDATIONS
1.1 Ground preparation
1.2 Excavations, piling and formwork
1.3 Reinforcement and concrete placement
2. SUBSTRUCTURE & DRAINAGE
2.1 Walls and columns
2.2 Waterproofing and ventilation
2.3 Sub-floor services
2.4 Ground floor
2.5 Drainage
2.6 Gas precautions
3. SUPERSTRUCTURE
3.1 Structural frame and/or loadbearing walls
3.2 External envelope
3.3 Cavities and insulation
3.4 DPCs and trays
3.5 Chimney and flues
3.6 Intermediate floor structure
3.7 Lintels beams and other structural elements
3.8 Balconies including fixings and weather proofing
3
4. ROOFS
4.1 Framing
4.2 Pitched roof coverings
4.3 Flat room coverings
4.4 Ventilation and underfelt, insulation
and fire stopping
4.5 Flashing, gutters and downpipes
5. FIRST FIX
5.1 Windows and doors
5.2 Floor decking ad stairs, sound proofing
and fire stopping
5.3 Services – electrical
5.4 Services – plumbing
5.5 Services – ventilation
5.6 Non-load bearing and compartment walls
5.7 Plaster and dry lining to walls and ceilings
6. SECOND FIX
6.1 Services – electrical including equipment
6.2 Services – plumbing including equipment
6.3 Joinery
7. SURFACE FINISHES
7.1 Internal finishes
7.2 Floor finishes
7.3 External finishes
8. FIRST FIX
8.1 Retaining walls and free standing walls
8.2 Hard and soft landscaping
Score Logic
4
Builder Feedback
1. Site Level
5
2. Senior Management
6
7
8
Its not always the site team’s fault
Input
9
Process
Output
Opportunities for improvement
Design /
Planning
Feedback
Compliance &
Buildability
checks
Build
Procurement
Contractual
10
Build Stage Summary– 4.2 Pitched Roof Coverings – Score 5
Attention to detail on hips, verges, ridges and valleys was evidenced
across the plots with good fixing details and mortar bedding to the tiles
being of a uniform colour. Tight, neat looking interfaces of materials and
elements deserves to be noted with particular attention given to the
straightness and tidiness of hips.
Key Considerations
The Site Manager inducts all trades onsite
emphasising expectations of required
Standards and quality. This is further
reinforced by the trades `Best Practice Guide`
produced by xxxxxxx Manchester, and quality
signoff process, requiring the Site Manager
and Quantity Surveyor signoff prior to
releasing payment of works.
11
12
Build Stage Summary– 4.2 Pitched Roof Coverings – Score 2
The pitched roof coverings on site were of a poor standard and did not comply with
the technical requirements. Saw marks were noted to the installed GRP valleys and
surrounding tiles with some cut tiles clipped and others not. Batten edges were not
treated in accordance with the technical requirements.
Key Considerations
Roofing contractors are struggling
to employ trades which have the
knowledge and competency to
carryout roofing works
to a good standard. Lack of
understanding from trades
around what `good looks like`,
no manufacturer installation
details onsite.
13
14
Builder Feedback
1. Site Level
15
2. Senior Management
Senior Management Feedback
Looking at the detail…
16
One NHBC: Driving Standards
Claims /
CSS /
Inspection
CQRs /
CIs / PiJ
Industry
Activities
Smart Data
CQR Builder Feedback
17
18
(Requires Improvement)
(Poor Quality)
(Very Poor Quality)
(Sites Scoring 3 or 2)
3.6 Intermediate floor
structure
3.5 Chimneys and flues
3.4 DPCs and trays
3.3 Cavities and
insulation
3.2 External envelope
3.1 Structural frame
loadbearing walls
and/or
2.6 Gas precautions
2.5 Drainage
2.4 Ground floor
SUPER-STRUC
2.3 Sub-floor services
2.2 Waterproofing and
ventilation
2.1 Walls and columns
SUB-STRUC
1.3 Reinforcement and
concrete placement
Site Address
Site Reference
Min Score
Max Score
Number of Sites
Standard Deviation
% of sites scoring 3
rovement)
% of sites scoring 2
% of sites scoring 1
ality)
3 or 2) Overall Rank
Population Rank
1.2 Excavations, piling
and formwork
e
1.1 Ground preparation
SID
FND
Build Stage
2.0
1.0
1.0
1.0
1.0
2.0
2.0
2.0
1.0
1.0
1.0
1.0
1.0
2.0
2.0
5.0
5.0
5.0
6.0
6.0
5.0
6.0
5.0
6.0
5.0
6.0
6.0
6.0
4.0
5.0
15
52
102
201
162
80
209
137
41
197
289
306
292
12
275
0.80
0.85 0.78 0.82 0.88 0.67 0.81 0.79 1.18 0.83 0.81 0.96 0.92 0.66 0.67
7%
6% 19% 24% 33% 33% 38% 36% 17% 29% 31% 41% 40% 33% 27%
13%
2%
5%
3% 14%
3% 10%
6% 12% 12%
6% 13% 20%
8%
2%
0%
4%
1%
1%
1%
0%
0%
0%
7%
1%
1%
2%
1%
0%
0%
29
38
28
25
5
15
3
11
23
12
14
2
1
10
24
38
37
31
19
11
28
5
18
33
9
4
2
1
35
10
Build Section Level - Percentage of Sites Scoring 4 (Good)- 6 (Outstanding)
1. Foundations
8. External Works
7. Surface Finishes
90%
80%
70%
60%
50%
40%
2. Substructure &
Drainage
Group level (6507)
Central (816)
3. Superstructure
South (3416)
Industry Total (17782)
6. Second Fix
4. Roofs
5. First Fix
19
North (2275)
Substructure & Drainage - Percentage of Sites Scoring 4 (Good)- 6 (Outstanding)
2.1 Walls and columns
2.6 Gas precautions
80%
70%
60%
50%
40%
30%
Group level (830)
2.2 Waterproofing and
ventilation
Central (108)
South (426)
Industry Total (2254)
2.5 Drainage
2.3 Sub-floor services
2.4 Ground floor
20
North (296)
Joinery - Percentage of Sites Scoring 4 (Good)- 6 (Outstanding)
80%
70%
60%
Group Level (260)
50%
Industry Total (692)
40%
South (146)
30%
20%
Central (27)
10%
North (87)
0%
21
Very Poor
Poor
Requiers
Requires
Improvement
Improvement
Good
Very Good
Outstanding
DPCs & Trays (Superstructure)
Stepped cavity trays where installed successfully
 Use of truss template
 Good supervision
 Known trades
 Site specific QC measures
 House type details reviewed and amended
22
DPCs & Trays (Superstructure)
23
DPCs & Trays (Superstructure)
Issues observed
• Missing or incorrectly positioned, particularly on peripheral
parts eg Bay windows
• Mortar joints not raked out for lead flashing
• Evidence of mortar debris on trays
• Limited drawings / details & knowledge within trades &
Management
• Limited quality checks
24
DPCs & Trays (Superstructure)
What produced good quality
• Details available on site (e.g. section drawings)
• Early discussions with trades
• New trades to site thoroughly inducted
• Importance
• Details provided to trades
• Benchmark agreed
• Stage checklist in place and being used
• ‘Focus areas of the month’ details displayed
• Templates and void formers always used
• Joint quality inspections (Site Manager & SC lead)
25
DPCs & Trays (Superstructure)
26
CQR Workshop
Vision (Results)
• Feedback results – Gain Priority, Identify what and why
Focus Areas (Analysis)
• Build areas at Industry / Group / Division level
• Risk, Profit ££££
Direction (Response)
• Business Change - Design / Procurement / Construction
• Training
27
Follow up / Interim meeting - Embedment
Progress update
• Interim results (Division / Group and Industry level)
• Comparison analysis
• Focus on trends
• Quality Indicator (Annual Comparisons)
• Business change management
28
How can CQRs Benefit You?
Quality
Live view of build quality (SMART data)
Platform to promote best practice
(enriched with photos)
Improve & track build and finish quality
Improve consistency
Reduce defects
Impartial view of quality
Financial
– Reduce remediation costs
– Commercial return (better profit, time &
cost of Customer Care)
29
Process
– Instant warnings of key issues / root
causes (Group / site specific) before a
defect manifests
– Real time clear focus and direction in
build quality at Industry / Group &
Division level
– Move focus on frontend processes rather
than backend (firer fighting)
Reputation
– Reduce customer complaints
– Reduce risk to brand and image
– Improve ‘Customer Satisfaction’
levels
Customer Feedback
30
Site Level - Promoting good practice
31
CQR Summary
CQRs
• Undertaking 4,000 CQRs PA
• Build Stage Summaries – Review 72,000 Build Stages PA
• Key Considerations – Identifying ‘Why it has occurred’ on extreme scores
• Visit 30 Major Builders PA, Top 4 at Regional Level, c.100 Builder meetings PA
• Key Trends – What is occurring at Site, Group and Industry level both positive and
Analysis negative and Why (Root Cause)
• Actions – Direction / Focus with Clear Vision & Clarity
Impact/ • Motivational driver for change – Risk, Profit ££££ (Change behaviours)
Benefit
•Evaluation of Success - Quality Indicator, Monitor progress of actions, Record impact
Follow-up by comparing additional CQR results
32
Visit: www.nhbc.co.uk/CQR
Call: 0344 633 1000 and ask for ‘CQR’
Or Email: [email protected]