Energy

Energy assessment

The building featured replacement PVC double glazed windows, a minimal level of attic insulation and a modern gas boiler before the works were undertaken. It is noted that, being detached, the house has the largest heat loss area to floor area ratio (2.51) of all the case study houses and a relatively high exposed wall area to total heat loss area ratio (0.48).

The building had a BER rating of F (401 kWh/m2.yr) prior to the works being carried out.

Areas: Floor areas following works.

Ratios: The heat loss area/floor area ratio indicates the compact envelope of the house – an important factor when considering wall insulation. Similarly, the window area/floor area ratio indicates the windows’ contribution to heat loss. 

Energy rating: BER/DEAP assessments were undertaken before and after the works which give a measure of the improved BER rating of the house. BER ratings are measured on a scale of energy consumption (kWh) per m2 of floor area per year (kWh/m2/yr), which is referred to as the energy value. 

Energy: Heating costs are estimated using energy consumption from DEAP and current fuel prices. Estimated costs can often be much higher than reality as the software assumes both a standardised heating pattern and temperatures throughout the house that may not reflect reality. Similarly, the actual costs can be higher if house owners exceed the standard heating pattern or assumed ventilation rates.