IEA task 13 advanced low energy dwellings, Danish participitation

This project forms the Danish participation in an international IEA working group, which scope was to gather and process monitoring results from 15 low energy houses designed and build during the IEA Solar Heating and Cooling Programme, Task 13 project. Only a few of the houses were built in time for a whole year of monitoring within the frame of the project. Therefore the IEA expressed their interest in forming a small working group that ended up with only two countries involved: Denmark and Holland. The gathering of monitoring results was performed by elaboration of a comprehensive questionnaire, which was sent to all 11 former participating countries. Twelve out of fifteen possible answers were received. The outcome of the project is a total overview of expected and measured energy consumption, the thermal indoor climate and the experiences gained from the house design as well from the many innovative technologies introduced in the buildings. On average the savings on the total energy consumption (heating, domestic hot water, electricity) amounts to 60% - a little less than the goal of 75%, but a fairly good result taking the experimental nature of the project into account. Besides, it has been shown in praxis that highly insulated buildings can achieve a very good indoor thermal environment without summer overheating problems if this is given the required attention during the design phase. The houses are all different and a wide spread of many different experiences are obtained. However, some general things have be seen in practically all the buildings: The required airtightness of the thermal envelope is hard to reach; ventilation systems often lead to annoying noise and draught; special attention is needed for avoidance of overheating by careful planning of the distribution of windows and choice of glazing type combined with automatic controlled venting and solar shading; installations and systems need to be simple and understandable for the habitant