Energy performance and indoor climate investigations in the passive house residential area Vallda Heberg

Abstract

Passive houses are becoming more common and the focus is usually put on the individual building. In the residential area Vallda Heberg, in the municipality of Kungsbacka in Sweden, all the buildings are built with passive house standard. The area consists of several different types of buildings; single family houses, apartment blocks, terrace houses, a retirement home and commercial buildings. All buildings are supplied with domestic hot water and heating energy from a local district heating system which is supplied with renewable energy generated on site. The actual energy performance of the buildings has been studied for up to one year and the results have been compared to the design values. The variation in the specific energy use due to the user behaviour is large in the premises and the largest variations were found in the domestic hot water use. The single family houses (with a full year of measured values of the specific energy use) had a lower specific energy use than designed, while the other buildings, according to a prognosis, could have a larger energy use than designed. In the single family houses the actual heating energy was lower than designed while the domestic hot water use and the operational electricity were higher than designed. The assumed household electricity in the single family houses was underestimated in the design phase. The measured indoor temperature in the premises is found to be in accordance with the recommendations of The Public Health Agency of Sweden and according to a survey most residents are satisfied with the indoor climate. The survey was sent to all the premises and the total response rate was 41 of 64. All questions referred to the perceived indoor climate during the winter season. While the most of residents perceived the indoor temperature as good, a common opinion was that the bathrooms were a bit cold while the bedrooms were experienced as too warm. The habits regarding airing were also investigated in the survey and large variations in this regard between the different types of premises could be seen.