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1Lessons from Exemplary Housing Renovations
Task 37 Advanced Housing Renovation with Solar and Conservation / Subtask B
May 2010 - PDF 6.18MB
By: Robert Hastings
Editor: Editor of the Brochures: Robert Hastings
60 exemplary housing renovations achieving dramatic energy savings have been documented in brochures as part of a project of the International Energy Agency*. This summary presents lessons learned from a collective look at these brochures from ten countries:
AT, BE, CA, CH, DE, DK, I, NL, NO and SE.
Austria - Apartment Building in Kierling
Building from the 1970’s with massive un-insulated walls, passive house standard insulation, new 90 m2 DHW solar heating, annual energy demand 68 kWh/m2
Austria - Apartmenthouse in Linz
Renovation to passive house standards, 91% space heating reduction. Special cellulose comb arranged behind a facade of glass panels.
Austria - Attic Conversion in Innsbruck
Conversion of the attic of a 19th century building; two new levels are built of connected wooden boxes. Special features are solar collectors and laminated wooden roof construction. Complies with Austrian low energy requirements.
Austria - Home for Elderly in Landeck
After renovating this home for the elderly, built in 1976, comfort was greatly improved. The wooden construction’s high insulation value and frameless glazing of the west façade minimize energy losses. The building complies with Austrian low energy requirements.
Austria - Housing in Purkersdorft
Renovation of a 19th century villa with four flats and constructed of 10 passive-house units. The 60 m2 solar system covers 28% of the DHW and space heating.
Austria - Single-family House in St.Valentin
Renovation of single-family house built in 1982 with vertical enhancement for a second housing unit. Special feature: A centralized ventilation system with heat recovery (efficiency 90%) combined with an air/air heat pump.
Austria – 19th Century Villa in Purkersdorf
Renovation of a 19th century villa with four flats, including ventilation system with heat recovery, solar panels and insulation of walls. After the renovation, the building is close to complying with Passive House standards.
Austria – Apartment Building in Kierling
Renovation of a 1970s apartment building, including central ventilation system with heat recovery, new insulation and windows, plus solar panels. Complies with Passive house standards, annual space heat demand is now 13 kWh/m².
Austria – Apartment Building in Linz
Renovation of an apartment building built in 1958: New façade with solar insulation system, ventilation system with heat recovery and air heating. After renovation the building complies with Passive House Standard, annual space heat demand is 11 kWh/m².
Austria – Apartment Buildings in Dornbirn
Renovation of five apartment buildings built in 1980. Central ventilation system with heat
Recovery and 5x30 m² solar collectors contributed to 59 % reduction of primary energy demand.
Austria – Detached House in Kufstein
Renovation of a detached house built in 1981 with a new facade and an enlargement of the living space. Important energy saving features are high insulation, triple thermopane glazed windows and an energy optimized modern shell. Solar collectors were installed for domestic water heating.
Austria – historic building in Irdning
Renovation of a historic building built in 1567, with four flats and two shops. Improved insulation, ventilation system with heat recovery and solar energy contributed to the 93 % reduction of energy demand.
Austria – Single-family House in Mautern
Renovation of a single-family house from the 1950s. Components of a Passive House, central mechanic ventilation system with heat recovery, air/air heat pump.
Austria – Single-family House in St.Martin
Renovation of a single-family house built in 1973 with an added storey for a second housing unit. A geothermal heat pump was installed and the building is ventilated by a mechanical system with 90% heat recovery and an earth to air heat exchanger preheats intake fresh air.
Austria – Summer Residence in Pettenbach
Renovation of a summer residence built in 1962. New features include: ventilation system with heat recovery and air heating, vacuum insulation panels and photovoltaic panels. Complies with Passive House requirements; 98% reduction of primary energy demand.
Belgium - Rowhouse Henz-Noirfalise
This 150 year old house needed a thorough renovation. The exterior was insulated with cellulose, new triple glazing was installed, the building is heated with solar collectors and pellets stove. 95% energy reduction.
Belgium - Semi-detached House in DePinte
Retrofit of a semi-detached house from the 50’s approaching Passive House Standard. The design focusedon sufficient insulation and airtight construction. Since the party wall faces south, windows were designed to make the best of available passive solar gains.
Belgium – 19th Century Building in Brussels
The existing roof structure was worn out and a new roof mandatory. The roof was removed and new apartments built in a light wooden frame construction on top of the building. Geothermal heat pump and solar collectors provide heat.
Belgium – Apartment Block in Wesenbeeck
Thorough renovation of an apartment block from 1959: Energy loss minimized trough insulation, heat recovery and thermal bridge alleviation. Solar collectors and pv panels installed.
Belgium – Conversion of Old Laundry in Brussels
Conversion and renovation of an old laundry into residential and office space. Insulation, solar collectors and PV installation contributed to the 70 % reduction of primary energy demand.
Belgium – Old Country House in Hershelt
Retrofit of a century old country house into a low energy house. The rural location of the project resulted in a very strict interpretation of the urban planning legislation. Energy reduction after retrofit: 88,5 %.
Belgium – Row Houses in Eupen
Transforming a 19th century row house into a Passive House led to 96 % energy demand reduction. Features include Ventilation with heat recovery, a ground-air heat exchanger, solar collectors, wood pellet stove and improved insulation.
Canada - Single Family House in Ontario
Retrofit of single family house included upgraded insulation (by use of polyurethane spray foam and also an insulated concrete form system), and adapting front porch and new extension roof for solar installations. Primary energy reduction: 81 %.
Canada – Single Detached House in Toronto
Retrofit project for an existing 1 1/2 storey house from 1946. The renovation, including among other features external foam insulation and solar energy applications, met the Net Zero Energy Healthy House (NZEHH) standards set out in a Canadian home design competition.
Denmark – Apartment Houses in Albertslund
14 apartment houses, in total 631 flats, were renovated in the period from 2007-2009. The renovation of the facade respects the original architecture and uses environmentally benign materials.
Denmark – Apartment Houses in Engelsby
Renovation included added insulation of facade/roof, new heating system and new water installations. Other features: Solar panels for domestic hot water, demand controlled moisture regulated ventilation and glazed balconies.
Denmark – Row houses in Albertslund
Aim of renovation: Compliance with the Danish standards for low energy class 2. Measures: Insulation, new windows, solar collectors and mechanical ventilation with heat recovery.
Germany - Apartment Building Blaue Heimat
Building under historical preservation protection, substantial renovation with redesign of floor plans. Heating supply by CHP combined with peak load boilers and water storage. 84% energy reduction.
Germany - Building Ensemble in Freiburg
Due to historical preservation protection, only attic and façade were set with new insulation. Use of combined heat and power technology, based on biomass (rape seed methyl ester). Calculated reduction of primary energy demand: 95%.
Germany – an 1892 Apartment Building in Ludwigshafen
Renovation of an apartment building built in 1892. To preserve the character of the exposed brickwork, 80 mm of interior insulation was used. The building was monitored for 1 1/2 years to study the interior insulation.
Germany – Apartment Building in Frankfurt am Main
The renovation of two postwar period apartment buildings, lead to a 94 % reduction of annual heat energy demand, almost meeting the Passive House Standard (energy balance computed using the Passive House Planning Package (PHPP)).
Germany – Apartment Building in Freiburg
Two similar apartment buildings from 1961 with different ventilation systems; mechanical ventilation with heat recovery (60 kWh/m²a heat demand), and exhaust air ventilation (65 kWh/m²a heat demand).
Germany – Apartment Building in Heidelberg
Building under historical preservation protection going through substantial renovation with redesign of floor plans, insulation of the building envelope, central heating system based on combined heat and power (CHP).
Germany – Apartment Building in Ludwigshafen
Renovation of a 1960 apartment building resulted in a 94 % reduction of annual heat energy demand. New features include extensive insulation, decentral ventilation system and PV roof (12.8 kWp).
Germany – Apartment Building in Ludwigshafen
Renovation of a 1960 apartment building resulted in a 94 % reduction of annual heat energy demand. The building complies with Passive House Standard; annual heat energy demand is 14 kWh/(m²a).
Germany – Apartment Building in Nürnberg
Renovation of an apartment building built in 1930 resulted in 87 % reduction of annual heat energy demand. In cooperation with the Passive House Institute (PHI) a concept for an external airtight layer was developed.
Germany – Apartments and Nursery in Ulm
Renovation of apartment with kindergarten included new windows, floor insulation, single room heating control and exhaust and supply HVAC with heat recovery.
Germany – Historical Building in Bavaria
Conversion of former military area built in 1888 into residential lofts and a medical center. Interior facades and roofs were insulated, Passive House Components were used, thermal bridges minimized. Energy is now supplied from biomass and solar power.
Germany – Nursing Home in Stuttgart
Overall renovation of building envelope and technical services. The main heat supply is a thermal power station (100 kW with 50 kWelec). Two gas burners (310 kW) provide back-up. Result: 65% reduction of primary energy.
Germany – Rectory in Ulm
Retrofitting of the building envelope and the building technical equipment. New features include solar collectors, improved insulation, single room heating control and exhaust and supply HVAC with heat recovery.
Germany – Row House in Mannheim
Renovation of apartments built in the 1930s and 1950s. Heat for the 12 flats is generated by a gas-fired condensing boiler and a combined heat + power Stirling engine. Each flat is provided with a separate high-efficiency ventilation unit placed on the attic floor.
Italy – Historical Building in Modena
Renovation of historical building damaged by moisture. Renovation included insulation of the building envelope, improved frames and removal of the superfetation (extension of building that deface the construction) to improve thermal radiation.
Norway – Apartment Buildings Myhrerenga
The apartment buildings erected in 1967-1968 were in need of major renovation. The renovation included, among others, blown in insulation in the roof construction, extra insulation in external walls and balanced ventilation system with high efficiency heat recovery.
Norway – Log House in Kongsberg
Built as a holiday cottage in 1942 using 6” logs, and converted into a permanent residence in 1997. The renovation was made in several stages and comprised the building envelope and a new ventilation system.
Norway – Row House in Oslo
Typical row house in the end of a three unit row, built in 1962, with poor insulation and thermal bridges. Renovation included internal vacuum insulation and installation of an integrated ground to water heat pump.
Norway – Single Family House in Orkanger
Renovation of a 1982 single family house including new roofing, balanced ventilation system with highly efficient heat recovery, better windows and insulation, highly efficient wood stove and heat pump.
Norway – Terraced Apartments in Stjørdal
The renovation of the terraced apartments from 1970 was first large low-energy housing renovation project in Norway. It included, among other measures, improved insulation, reduction of thermal bridges and a balanced ventilation system.
Sweden - Apartment Building in Alingsas
The Brogarden housing estate with 300 apartments built in 1970. Better insulation, heat exchanger and solar heating system bring the annual heat demand down to 55 kWh/m2.
Sweden – Apartment Building in Alingsås
300 apartments constructed in 1970 to be renovated to passive house standard. Measures include added insulation (ground floor, exterior walls and roof), new facade material and new windows.
Sweden – Apartment Building in Backa
In Backa outside Göteborg, the public housing company Poseidon has been renovating their apartments, built in the 70s. The renovation process continues, with focus on energy, first in a demonstration project.
Switzerland - Apartment Building in Ostermundigen
60% heating energy reduction of 1960's building, new apt. layouts, new sunspaces and penthouses, innovate heat recovery system.
Switzerland - Apartment Building in Staufen
65% reduction of primary energy, two stage renovation: envelope then tech. systems, 110 m2 roof-integrated PV, new deeper thermal-bridge-free balconies.
Switzerland - Apartment Building with Shops in Zurich
75% energy reduction in urban apt. building with historic protected façade, prefab new roof modules for new attic penthouse.
Switzerland - One-Family House in Walenstadt
80% reduction in heating energy, solar drain-back combi dhw-heating system, new architecture.
Switzerland – Apartment Building in Zurich
Renovation of an 1898 apartment building in poor condition. A 75 % reduction of primary energy demand was attained.
Switzerland – Apartment Building in Zürich
The renovation included new façade to the street, new ground floor architecture, roof-integrated PV panels and solar thermal collectors. Primary energy demand was reduced by 89 %.
Switzerland – Apartment Building Volketswil
Renovation of an apartment building in a suburb of Zürich. The goal of higher energy efficiency was achieved by adding insulation to the façades, solar collectors on the roof, plus a new ventilation system.
Switzerland – Apartment Towers in Geneve
Renovation of three small apartment towers built in 1954. Due to historic preservation, two buildings were renovated with external insulation of the walls, and one with internal insulation.
Switzerland – Historically Protected Senior Residence in Bern
Renovation of a historically protected senior residence built in 1872 with an extension to the rear of the west wing, new floor plan layout and energy saving measures, including new insulation and mechanical ventilation with heat recovery.
Switzerland – Single Family House in Lanterswil
Modernization of a single family house. One of the heat loss reduction measures is a passive solar façade that absorbs and stores solar energy to create a warm buffer between the house and the ambient. Additionally, PV panels (4,9 kWp) were added.
Switzerland – Single Family House in Ostermundigen
Improved insulation, structures for utilization of passive solar energy, a PV system (6.6 kWp), solar thermal collectors and a geothermal heat pump result in net energy production (10 kWh/m²a).
Switzerland – Single Family House in Walenstadt
Renovation of a single family home led to an 80 % reduction of primary energy demand. New features included insulation of building envelope and new windows. Pellets stove and solar collectors were installed.
Switzerland –Two-Family House in Stansstad
Comprehensive renovation of building built in 1962. Work included elimination of thermal breaks, new central ventilation system with heat recovery, central wood pellet stove (8 kW), solar collectors. Complies with the Swiss Minergie-P Standard.
The Netherlands – Row Houses in Roosendaal
Planned renovation of row houses built in 1965 to Passive House Standard. New features include new timber frame facades and roofs, innovative heating and solar collectors.
The Netherlands – Row Houses Kroeven in Roosendaal
First large-scale Passive House renovation project in Holland, the subject is a social housing project built in 1967. Innovative building technology and process have been applied. A 90 % primary energy reduction was achieved.
The Netherlands – Single Family House in Sint Pancras
Renovation of single family house dating from 1939. Aims: reducing fossil energy demand by a factor 7 and later even become net energy positive due to utilization of solar energy (PV and collectors).