Energy

Energy assessment

(The basement is currently unoccupied and was excluded from the assessment.)

The owners carried out some basic retrofitting when the house was purchased in 1996. Basic attic insulation (100mm fibreglass) was installed to the main roof, and the external walls of the return block (kitchen/dining area) were dry-lined and insulated. The roof of the return was reconstructed and insulated to the standard of the day.

A gas-fired central heating system was installed for the first time, with a single zone and timeclock for the whole building. Heat delivery is controlled by thermostatic radiator valves. Window repairs gradually carried out over the years have helped reduced draughts and air infiltration.The building’s condition gives it a BER rating of D2 (266 kWh/m2.yr).

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.