Type of construction: Renovation of existing building
Typology: Residential, multistorey
Construction systems: Lightweight concrete
Location: Estonia, Saue
In Estonia, more than 70% of the residents live in apartment buildings constructed before 1990. The majority of those buildings have the same problems: high-energy consumption levels, insufficient ventilation, uneven indoor temperatures, and insufficient thermal comfort levels. The world’s population is becoming increasingly urban and this trend is expected to increase. Demolition of existing buildings and reconstruction with tightened land-use standards for new buildings are not the realistic strategy in Estonia, due to the fact that 82% of the dwellings are privately-owned. Therefore, extensive, ‘deep’ levels of renovation work are required. Possible solutions are the extension of rooftops and living area by closing open balconies, which can eliminate thermal bridges and improve the usability of the dwellings and increase the indoor comfort.
We realised a deep energy retrofit with the extension of an existing apartment building. The building has a high level of replicability in Estonia and other countries in North-East Europe, being an example of lightweight concrete construction located in Saue, Estonia.
The average primary energy use before the renovation was 211 kW/(m2a). As the indoor climate was insufficient (low ventilation, low temperature), the normalised primary energy use should have been around 274 kW/(m2a) (176 kW/(m2a) for heating). One year after deep renovation the avarage primary energy use was measured to be 93 kW/(m2a) (53 kW/(m2a) for heating). To minimise environmental impact and disturbance to residents, the envelope was constructed in prefabricated modules with maximum locally re-used and recycled materials and locally based bio-based materials. This construction method resulted in a short construction period on sites and occupants were less disturbed. It was more weather-independent as well.
Find the technical drawings (plans, sections, etc) here.
We achieved the following results in Estonia: