Before retrofit: BER D2
After retrofit: BER A1
The challenge: Bungalow built in 1978, with extension added in 1989. Cold and draughty, does not retain heat when boiler turned off. Oil fired central heating. Inefficient windows and doors.
Property Type: Bungalow
Year of Build: Original house 1978, extension added in 1989
Homeowner Goals
To create a warm, comfortable and healthy home that would retain heat and to future‑proof the property.
Before & After Retrofit Summary
| Category | Before Retrofit | After Retrofit |
| BER Rating | D2 | A1 |
| Overall Comfort | Cold, draughty home that lost heat quickly when heating was turned off | Consistently warm, comfortable and stable internal temperatures |
| Heating System | Oil‑fired central heating via range cooker with open fire | 6kW air‑to‑water heat pump with modern controls and wood‑burning stove |
| Fuel Type | Fossil fuel (oil) | Electricity with renewable contribution (heat pump & solar PV) |
| Insulation – Attic | Approx. 100mm insulation | Upgraded attic insulation to minimum 300mm |
| Insulation – Walls | Full fill insulation in the cavity of the original house | Cavity wall insulation completed and full external wall insulation applied to original house and extension. |
| Windows & Doors | Older, inefficient windows and doors | High‑performance triple‑glazed windows and doors |
| Airtightness | Significant uncontrolled draughts, open chimney | Airtightness measures implemented and chimney sealed |
| Ventilation | Natural hit‑and‑miss vents (manual, inconsistent) | Mechanical Ventilation with Heat Recovery (MVHR) |
| Indoor Air Quality | Variable, dependent on manual vent use | Continuous fresh air with heat recovery |
| Attached Garage | Leaky roller shutter door and poor‑quality internal door between the garage and kitchen. | Improved thermal separation as part of overall fabric upgrade |
| Pipework | Pressure test to determine if existing pipework sufficient identified an above ground leak. | Leak repaired following pressure testing, pipework retained |
| Electrical System | Partial upgrade required | New 16sq main cable, 10sq earth cable and earth rod installed |
| Renewable Energy | None | 4.3kW solar PV system installed |
This project demonstrates how an independent, whole‑house approach can transform an older bungalow into a comfortable, energy‑efficient A‑rated home.
