Decreasing energy use of industrially produced multi family dwellings in Sweden

Building as many houses as possible in a factory environment seems like an effective way to systematically reduce productivity costs and improve quality in the building process. Based on this idea, a Swedish company has manufactured modules consisting of one or several rooms that were transported and assembled into multi family dwellings onsite. This paper analyses different improvements regarding the energy use of the building, particularly for changes in thermal insulation, air tightness and ventilation system. The annual energy use for a normal year is calculated for a theoretical house and compared to actual houses in use from this manufacturer who is located in Malmö, Sweden. Life cycle costs were calculated for each alternative over a 50 year period. With the assumed discount interest rates, almost every proposed alteration should be beneficial both individually and in combination