The case study deals with Site 104, a 2 Storey Detached House with a pitched roof. The dwelling has a total floor area of 215.6 m2. The wall construction from the interior consists of internal plasterboard finish to 70 mm service cavity filled with Poroc Rockwool insulation. All windows fitted are triple glazed with argon filled low emissivity glass with a typical U-Value of 1.24 W/m2/K; hot water will be controlled by a separate zone to provide time and temperature control. Furthermore, the house has a REC Indovent-Rt4005-EC mechanical heat recovery ventilation system.