Use of energy-signature method to estimate energy performance in single-family buildings

Abstract: The renewal of the existing housing stock is a slow progress and theexisting is quite old. The existing housing stock represents a largeamount of the bought energy need for heating and a simple method forquickly determining the energy performance is needed.There are many different methods for estimating the energyperformance of buildings. In this report the feasibility of using asingle-variate steady state method to investigate energy performancehas been tested. Bought energy need in single-family houses in a coldclimate has been observed during the cold period. The observationshave been made with the help of a measurement system requiring aminimal installation. The heat loss factor of the observed buildingshas been determined using the energy signature approach and differenttime scales have been tried.The result shows that to determine the heat loss factor of single-familybuildings, a single-variate method is valid. Daily averages are a goodtime scale for houses using radiators under the windows to heat thebuilding. Buildings with floor heating in concrete slab need to have alonger time scale, around 3 days.The method does not account for occupancy levels and separateenergy use in specific installations is not easy to estimate with theminimalized measurement setup. A combination of heat sources suchas district heating, electrical heating, heat recovery and/or fire stove isproblematic to handle with the energy signature method if enoughobservations for al heat sources can be achieved.