A deep retrofit to a challenging listed building that shows energy efficiency is applicable to the entire housing stock.
This grade II listed townhouse had been used as an office space for a century. The conversion back to a family home allowed for a deep low-energy retrofit to occur alongside best practise conservation. The terrace form provided a desirable form factor. By adding modest amounts of insulation and an innovative window upgrade the performance of the house has been transformed from gas guzzler to near Passivhaus.
TFA 367sqm. Form Factor 1.9. U-values of walls and roof 0.15W/m2K, floor 0.2W/m2K. Average whole window/door U values 1.0W/m2K. Heat demand 21 kWh/m²a, Heating load 16W/m2. Final air-tightness result 1.1 ach@50Pa.