PASSIVHAUS PLANNING PACKAGE (PHPP)
The Passivhaus Planning Package (PHPP) developed by the Passivhaus Institut in Germany adopts a different methodological approach to dealing with non-repeating and geometrical thermal bridges than that incorporated within SAP. In PHPP, the heat loss calculations are undertaken using external envelope areas, rather than internal envelope areas (see figure below).
SAP – internal envelope dimensions used
PHPP – external envelope dimensions used
Differences in the dimensions used within SAP and PHPP
Irrespective of which methodological approach is adopted, SAP or PHPP, both should give similar results.