September 2013
Passive House CASA SANDOR Case Study
It is intended to be a passive house adapted to the climate conditions in Romania. It is a private
project started as a low energy house, which during execution, under the guidance of the
specialists from the Passive House Association of Romania, turned into a passive house.
The estimated energy demand as scheduled in accordance with PHPP 2007 (programme
developed by PHI - Darmstadt) is only 15,25 kWh/m2/y for heating the space to achieve the
thermal comfort, and energy consumption for primary energy required 59 kWh/m2/y.
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September 2013
Passive house CASA SANDOR
This case study outlines a single-family house according to the Passive House concept, adapted to the Romanian climate
conditions. It was developed under private financing.
GENERAL
Name: Passive House CASA SANDOR
Owner: Iosif SANDOR
Designer: Arh. Cristina UNGUR
SC STIL PROIECT CLUJ
New/retrofit: New
Use: Residential
Location: Cluj Napoca, România
Climate: Humid continental
Heated area: 240 m2
Investment cost: 700 €/m2
Certification: Awards: -
The house is situated in Laterala Street ,12, Cluj Napoca
in a residential area; GF, P +1
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DESIGN
Approach: Passive House design
Construction typology: Heavyweight construction
U-values W/K/m2: walls 0,12; roof 0,11; windows 0,80
Air tightness: 0,60 h-1 at P=50 Pa
Ventilation: mechanical with heat recovery
Passive heating strategies: solar passive design
Passive cooling strategies: canadian well, solar
protections
ENERGY
Primary energy need: 59 kWh/m2/y
Final energy consumption: 22,7
kWh/m2/y
CO2 annual emissions: 15,4 kg CO2/m2/y
Energy rating: A (energy class)
Specific space heat demand:
15,3 kWh/m2/y
RENEWABLE ENERGY
Sources: Geothermal energy (canadian well)
PV installed power: Solar thermal installed power: Biomass installed power: Other RES power: Annual RES generation: N/A
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GENERAL
Passive House CASA SANDOR
BUILDING
Name: Passive house CASA SANDOR
Use: Residential
Users: 3 residents
Completion year: 01.12.2009
New/Retrofit: New construction
Type of ownership: Private
Building/community:
The single-family detached house with S+P+1 floors, has a rectangular shape with compacity. Using appropriate
shadings of the building itself, there are no significant shading elements in the vicinity of the building
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GENERAL
BUILDING
Building description:
The building is defined by its cubic form.
It consists:
Basement – technical room, fitness room, deposit
Floor – Living, kitchen, bathroom, office
First Floor – 2 bedrooms, 2 baths, dressing room
Area and volume (m2, m3):
Net floor area: 240 m2
Gross floor area : 313,9 m2
Heated area: 240 m2
Cooled area: Floor height: 3,0 m
Gross total volume: 720 m3
What is special?
The building has a green roof.
LOCATION
Location: Cluj-Napoca, Romania
Population: 325.000 inhabitants
Site: Urban
Local resources: No local energy resources used.
No exploitation system already available.
Water resources: No natural water resources are
used by the building.
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GENERAL
CLIMATE
Climate description: Humid continental climate (Köppen climate classification)
Heating degree days (base temperature 12/20) : 3070 for a standard building
Cooling degree days (base temperature 25) : 101
Mean annual temperature : 8,3˚C
Amount of global radiation per year: 1260 KWh/m2
Minimum monthly average of radiation per day: 1,09 kWh/m2
Maximum monthly average of radiation per day: 5,82 kWh/m2
Location source: Latitude North -46,47, Longitude East – 23,38, Altitude - 410 m
(Weather database: Meteonorm Cluj Napoca)
ACTORS
&
AWARDS
Owner: Iosif SANDOR
Designers: Architects – STIL PROIECT SRL, Energy experts – ECOCALD SRL
Construction company: BAULAND CONSTRUCT ROMANIA
Supporting actors: ISPE Bucharest
Awards: -
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GENERAL
COSTS
&
FINANCING
Building and RES investment :
Total construction cost including RES (on-site),
167.760 €
Cost of renewable energy systems : 15.000 €
(canadian well)
Construction Cost: 636,5 €/m2 net floor (without RES)
RES cost: 62,5 €/m2 net floor
Standard cost in the region: Reference cost for the
same type of building - 800 euro/m2
Financing scheme: It was paid entirely by the owner
IMPLEMENTATION
Implementation process:
• Several changes to the initial design were made in
the implementation process thanks to the expert
suggestions - Passive House - ECOCALD SRL.
• Initial shading solution was later executed, after
the first year of operation.
Next time:
• To elaborate a geo-technical study exactly on the
construction site.
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GENERAL
USERS
User behavior:
The owners were instructed on how to make the best
use of the interior installations by the expert in
Passive House - ECOCALD SRL.
User feedback:
Building owners are satisfied with the building
perfomance and its comfort. They always welcome
on-site visits ready to provide valuable information
about the construction itself and about the actual
operation of the house.
COMMISSIONNING
Energy commissioning: The building is not under
monitoring in terms of real energy consumption.
Gap: There is a gap between design and reality. The
owners have dropped the idea of installing the PV
panels foreseen in the initial project because of
complicated procedures for network connection
existing Romanian legislation.
Comfort commissioning: The building is not under
monitoring in terms of thermal comfort (temperature,
relative humidity).
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DESIGN
Passive House SANDOR
DESIGN APPROACH
Approach: Passive house design
Goals: Energy goals to achieve the passive house
consumptions
Design methodology: A very reduced energy demand
for heating / cooling with a very good building
insulation
Motivation: Low energy consumption
Key points:
• compact construction
• efficient insulation
CONSTRUCTION
Construction typology:
Compact construction with ICF – BAUCELL masonry
Thermal insulation: NEOPOR – BASF System
Daylighting: Daylight use was not set as priority thus
no daylighting devices been installed.
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DESIGN
DETAILS
Façade: masonry BAUCELL:
5 cm – NEOPOR insulation + 15
cm reinforced concrete + 20 cm
NEOPOR insulation.
U-value = 0,12 W/m2K - thermal
bridges are included
Windows: APLAST triple glazing
and low-e
Uglass = 0,6 W/m2K
REHAU
PVC
frame
with
poliurethane foam
Uframe = 0,83 W / m2K
Uwindow = 0,80 W / m2K
Roof: BAUDER green roof,
insulated with 30 cm NEOPOR
U-value = 0,11 W/m2K - thermal
bridges are included
Thermal bridges: -values
• for windows: lintel 0,029
W/mK, outline 0,016 W/mK
• ground plate 0,031 W/mK
No important punctual thermal
bridges ().
Ground floor: Parquet, OSB
panel, lightly reinforced screed
5 cm, extruded polysterene
foam 25 cm, reinforced
concrete screed 15 cm.
U-value = 0,16 W/m2K - thermal
bridges are included
Thermal
inertia:
concrete
floors, concrete roof, concrete
pillars, concrete masonry
PASSIVE STRATEGIES
Passive heating: Passive strategies for drastic reduction
of heating needs: insulation, ventilation with heat
recovery, solar gains.
Passive cooling: Passive strategies for drastic reduction
of cooling needs: insulation, canadian well.
Solar protection systems were implemented after one
year of exploitation. Non automated solar protection.
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DESIGN
AIR QUALITY
Ventilation type: mechanical with heat recovery
Air tightness: Blower door test results: 0,60 h-1 at
P=50 Pa
Ventilation solution: Mechanical ventilation with heat
recovery
Efficiency of the system installed: 0,9
Mean actual efficiency : 0,8
ENVIRONMENT
Water:
No strategy was implemented. District water network
is used.
Waste:
No strategy was implemented to manage waste.
INNOVATIONS
Technology:
Pluggit high efficient heat recovery system.
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ENERGY
Passive House SANDOR
ENERGY INDICATORS
Primary energy need: 14160 kWh/y,
59 kWh/m2/y – value from simulations
Primary energy need for standard building:
480 kWh/m2/y
Final energy consumption: 5448 kWh/y,
22,7 kWh/m2/y – value from simulations (weather
typical year)
CO2 equivalent emission: 15,9 kg CO2/m2/y
Accounting for 0,7 kg CO2/kWh (Romanian
conversion factor of electricity in CO2 equivalent
emissions)
Conversion factor FE-PE:
electricity: 2,6
Energy labels: National energy certification level: Building without
national energy certificate.
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ENERGY
ENERGY DEMAND
Heating demand: 15,25 kWh/m²/y
Cooling demand: 0 kWh/m2/y – design values
ENERGY SYSTEMS
Combined system:
• Heating system and DHW generation:
- Electrical central heating and hot water (LAING 2 + 2
KW) system
- Canadian well with diameter 200 mm and length 90
m + mechanical ventilation with heat recovery air /
air FOCUS 200 with 3-speed way of working
• Cooling system: Canadian well
Energy storage: No storage
Energy management system: No management system
installed.
Control and Automation: No controls or automated
elements.
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ENERGY
LIGHTING & APPLIANCES
Lighting:
The lighting devices technology: CFL, LED
Appliances:
The appliances are A++ energy class.
There is no real consumption monitoring system of
energy.
COMFORT
The values below are the values used for energy
simulations (building design)
Temperature set point (heating): 20 C
Temperature set point (cooling): 26C
Weather database: Meteonorm Cluj Napoca
COST
Electricity: 60 Euro monthly during winter
Electrical energy tariff – 0.14 Euro /kWh
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