Client:
Adele Rebel and Till Hahlbeck
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Hohe Strasse, Hanover
Description
The building was complete in need of renovation. The exterioir walls were partial damp and the building services completely outdated. On the attic floor, there were still some individual stoves or a gas-boiler. Damages due to damp to floor and ceiling beams were caused by the damaged roof. For the projected modernisation, only the exterior walls, ceiling and the base plate survived.
The three exterior walls as well as the base plate were equipped with a interior insulation. Frontage and roof were built in wood frame construction with 40 respectively 48 cm heat insulation. Minimizing thermal bridges succeeded through consequently separating existing primary structures from existing outside components and the carefully realisation of airtight taping. Therefore, conventional heating and a gas-connection were not necessary. Heating in winter is realised with a compact unit with smallest heat pump, passive heat transmission and the comfort ventilation system combined with heat revovery. In summertimes, a solar collector overtakes approximately the complete water-heating.
Involved parties
Design:
architectual office (21+), Hanover, and clients
Realization:
personal contribution
Building data
BUILDING TYPE:
Singe-family-house (backyard building with three exterior walls)
LOCATION:
Hanover-Linden
YEAR OF CONSTRUCTION:
before 1900 (rebuilt old stock)
MODERNIZATION:
2004
RESIDENTIAL UNITS:
1
HEATED USABLE SPACE:
ca. 120 m2
SUBSIDIES:
KfW, BAFA, proKlima
Initial condition
EXTERIOR WALLS:
24 cm single skin walls
HTC ? 1.8 W / (m² K)
WINDOWS:
Wooden or plastic windows with double glazing
HTC ? 2.6 W / (m² K)
ROOF:
completely without thermal insulation
HTC ? 5.2 W / (m² K)
BASEMENT CEILING:
uninsulated basement ceiling
HTC ? 2.4 W / (m² K)
VENTILATION:
Window ventilation as well as typical old building joints and cracks
HEATING:
Individual stoves and gas-boiler
Modernization in detail
EXTERIOIR WALLS:
on existing masonry exterior walls inside bearing wood construction with a total of 20 cm heat insulation, quality of 0.035 W / (mK), HTC = 0.14 W / (m² K)
South side (backyard): new wood frame construction with 12 cm heat insulation system, 20 cm insulation between wood cellular beams and 6 cm insulation between substructure, HTC = 0.08 W / (m² K)
WINDOWS:
Passive house windows with 3-pane glazing
HTC = 0.75 W / (m² K)
ROOF:
Wooden beams with 36 cm heat-insulation and substructure with 12 cm insulation, quality 0.035 W / (mK), HTC = 0.08 W / (m² K)
BASEMENT CEILING:
new construction on existing concrete floor: floor covering on particle board, wood beams with 30 cm insulation, quality of 0.0035 W / (mK), HTC = 0.11 W / (m² K)
VENTILATION AND HEATING:
Compact ventilation unit with integrated passive heat exchangers and micro-heat pump, solar water heating system, 5 m² absorber surface, 250-liter tank, heating the rooms exclusively via ventilation system and a radiator
COOLING:
no active cooling installed
Measured values
AIRTIGHTNESS:
n50 = 0,35 h-1
Calculated values
Calculation method: Passivhaus planning package; Initial values: Hanover building typology
HEATING ENERGY NEEDS:
BEFORE
300 kWh/(m²a)
AFTER
28 kWh/(m²a)
SAVINGS
91 %
TOTAL ENERGY NEEDS FOR HEATING,AIR CONDITIONING,DHW,ELECTRICITY:
BEFORE
GAS
458 kWh/(m²a)
ELECTRICITY
16 kWh/(m²a)
AFTER
ELECTRICITY
37 kWh/(m²a)
PRIMARY ENERGY NEEDS FOR HEATING,AIR CONDITIONING,DHW,ELECTRICITY:
BEFORE
555 kWh/(m²a)
AFTER
97 kWh/(m²a)
SAVINGS
83 %
CO2-EMISSIONS FOR HEATING,AIR CONDITIONING,DHW,ELECTRICITY:
BEFORE
122 kg/(m²a)
AFTER
23 kg/(m²a)
SAVINGS
81 %
