Fördjupad uppföljning av Flagghusen : Studie av inneklimat, ventilationssystem och vädringsbeteende

In new built apartments buildings with modern mechanical supply and exhaust ventilation, window opening was reported by a majority of the residents. A follow‐up study of the physical indoor environment and the perceived environment by the residents was therefore performed. The follow‐up study is included in a project which also comprises of a follow‐up of the energy use and factors related to this. The final report for the whole project “Fördjupad energiuppföljning Flagghusen, rapport version 0.2” present both the energy related study and the indoor study. The indoor study is also separately presented in this report.The aim of the indoor study was to examine the experience of the residents with a questionnaire survey including both the general indoor climate and their opening behaviour. One aim was also to perform more comprehensive examinations of the physical indoor climate and the performance of the ventilation system in some apartments in which window opening was reported for longer time periods.The results show that the indoor climate is in general perceived as good. A majority of the respondents still report opening the windows frequently and for longer time periods. 55% open daily/almost every day. 55% report they open for several hours or during the whole day/night. The reasons for opening the windows includes; experience of stale bad air, bad air quality, too hot, other ventilation is insufficient and habit, opening the windows as a routine.It is concluded that a majority of the respondents open the windows relatively extensive. Both the thermal climate and the air quality are reported as causes for experiencing a need of opening.Measurements of the physical indoor climate was performed in apartments where opening of the windows were reported. The operative temperature during winter conditions was between 21,5‐25,1ºC in the apartments. At 1,1 m above the floor the operative temperature was above 23ºC in all apartments but one. In five of ten apartments the temperature was exceeding 24ºC, a guideline value for homes. The ventilation supply air flow via the ventilations system were below the building regulation in five of eight apartments. In five of seven apartments the design air flow 4 l/s person was not fulfilled for the number of people staying in the master bed room during the night. A limited number of apartments were examined. However several factors were identified to cause the reduced air flows including experience of noise from the ventilations unit located in the apartment, limited knowledge among the residents about the function of the ventilations system and wrongly balanced air supply rates. The design of the systems, aiming at allowing a reduction of the air supply when people are not present, have also influenced the outcome. The interaction between the residents and the technical systems were identified as an important factor for the resulting indoor climate.Factors, which may reduce the thermal comfort and the air quality, were identified in all the three areas affecting the indoor climate; the design of the technical systems, the building envelope and the actions of the occupants.The findings in the project supports the importance of addressing the following factors in the design and operating stageFor the engineers* Ensure that the ventilation system do not cause disturbing noise in the apartment.* Ensure that a satisfying thermal climate can be achieved during both winter and summer time. This includes balancing of the heating and ventilation systems and sufficient solar shading.* Ensure that clear and understandable instructions exist on how the ventilation systems should be controlled, especially if the ventilations units are located inside the apartment.* Ensure that the supply air flow is sufficient for the number of people that may be present in the bed room. If children or infants are sleeping in the room these should also be included in the design values.For the residents* If too high temperatures are experienced during the heating season; reduce the heat emittance from the radiators first, before the windows are opened.* Use the solar shading that exist