Passive House Classic in Voynegovtsi

Passive House School’s team was involved in the design, energy modelling and construction of the certified Passive House Classic in Voynegovtsi.

The house is located on the southern slopes of Stara Planina. The house is situated on the highest part of the village of Voinegovtzi. It is surrounded by picturesque nature and it has superb views of Sofia and Vitosha Mountain.

The idea to build this family house is to show that the profitability, the comfort, and the environmental friendliness not only don’t contradict but rather complement. That’s possible, thanks to the Passive House Standard, in Bulgaria also. The house is built with materials produced in Bulgaria. Considering the profitability, designers had not intended to use renewable energy sources. They were mainly driven by the principles of the design of Passive Houses. The house has its own water source and Wastewater Plant.

Eco Construction Ltd., Vanya Draganova, Snejina Aleksieva
Building services
Tzvetomir Botev, Svetlin Dobrevski
Building physics
Svetlin Dobrevski
Krum Yankov
Craftsperson/parties involved
Bocal Engineering Ltd., Evrodom 2001 Ltd.
Passive House Consultant
Svetlin Dobrevski

Certified building
Passive House Classic new build

Treated Floor Area according to PHPP
152 m2

Construction type
masonry construction

Building type
detached single-family house

Sofia, Bulgaria

Air tightness
n50 = 0.2/h
press test result

Annual heating demand
12 kWh /(m2a ) calculated according to PHPP

Heating load
12 W/m2

PE demand (non-renewable Primary Energy)
88 kWh /(m2a ) on heating installation, domestic hot water, household electricity and auxiliary electricity calculated according to PHPP

Exterior wall
Interior plaster (0,18 W/(mK)), 15mm
Porotherm bricks (0,279 W/(mK)), 250mm
EPS greywall (0,032 W/(mK)), 250mm
Exterior plaster (1.4 W/(mK)), 20mm

U-value = 0.112 W/(m2K)

Basement floor / floor slab
Parquet (0,180 W/(mK)) 20 mm
Cement screed (1.10 W/(mK)) 60 mm
Reinforce concrete (2.30 W/(mK)) 160 mm
Gravel (1.50 W/(mK)) 940 mm
slab (2.30 W/(mK)) 400 mm
XPS (0,035 W/(mK)) 200 mm
Waterproofing (0,230 W/(mK)), 8 mm

U-value = 0.144 W/(m2K)

Interior plaster (0,18 W/(mK)), 15mm
Reinforce concrete (2.30 W/(mK)) 160 mm
XPS (0,035 W/(mK)) 300 mm
concrete (2.30 W/(mK)) 100 mm
Waterproofing (0,230 W/(mK)), 8 mm

U-value = 0.112 W/(m2K)

Alumil, S91
Aluminium profile, SWISSP. Ultimate
Uf: 0,78 W/(m²K)
U w-value = 0.85 W/(m2K)

Guardian – ClimaGuard nrG (6:/16/4/16/:6 Arg 90%)
U g-value = 0.69 W/(m2K)
g -value = 62 %

Entrance door
glazed door
U d-value = 0.8 W/(m2K)

Zehnder, ComfoAir 200
heat recovery unit with preheater for frost protection
eff. specif. HRE: 91%

Heating installation
ceiling concealed RAC single split

Domestic hot water
thermal solar system 5m², buffer storage tank, time controlled circulation

More detailed information about the project you can find here.

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