The influence of dwelling energy efficiency on the sensitivity of inputs to a steady-state energy model

The Standard Assessment Procedure (SAP) is a UK building regulation compliance tool for dwellings. SAP includes over 190 inputs to assess the energy efficiency of dwellings. However, uncertainty within these input parameters will impact energy demand assessments. A local sensitivity analysis is performed on 143 inputs for dwellings of varying energy efficiency to evaluate the influence of input parameters on total energy demand. Influential input parameters are shown to vary depending on the energy efficiency of the dwelling. The most sensitive parameters are heating practices of occupants, heat loss parameters of the dwelling (such as wall U-value and window U-value), building system efficiencies and occupant actions. Using improved estimates of these parameters is essential in reducing uncertainty in dwelling energy demand predictions.