This report consists of two parts, out of which the first deals with the planning and designing of a small house in the Swedish city of Huddinge, using the weather conditions of the Swedish city of Malmö. The house has to be in accordance with the Swedish building- and construction regulations, as well as with the limitations in energy consumption given. The house itself has to consist of at least two bedrooms, and blueprints of the house, various constructional elements, ventilation, sanitation and electricity have to be drawn. Calculations of these aspects also have to be made, to ascertain that the different parts function as they should, and that the dimensions are sufficient. The second part is called “Allergy free home”, and investigates how indoor climate affects us, and whether it has changed during the last few decades. It also makes an effort to see whether the increase of allergies and asthma is correlated with possible changes in indoor climate, and whether technical solutions might help to handle or even decrease the issues arisen. The main focus will be on dust mites and the effect they have on people with asthma, given that dust mites is the biggest factor regarding indoor climate and allergies.