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Draught-proofing is the fastest-payback job in home energy: brush strips for doors, self-adhesive foam or rubber seal for windows, a chimney balloon or sheep for unused flues (GBP 20 that saves ~GBP 40/yr on its own), letterbox brush, keyhole cover. The one rule: seal DRAUGHTS, not VENTILATION: leave trickle vents, air bricks and extractor fans alone, and never block the vents a fuel-burning appliance needs.
What The Draught-Proofing Savings Calculator Works Out
- Saving per year: the Energy Saving Trust's figures for a gas-heated home: about GBP 45 a year for professionally draught-proofing doors and windows, another GBP 40 or so for an open unused chimney once ballooned or capped, and GBP 120 or more once floors, skirting and the letterbox are done too.
- Payback: the materials cost divided by the yearly saving, in months. A hundred pounds of brush strip, seal, chimney balloon and letterbox furniture fitted over a weekend repays inside two winters, then compounds for the near-decade the seals last.
- Best pound-for-pound: the chimney balloon (GBP 20 saving about GBP 40 a year) and the front-door brush strip. Unlike every other efficiency measure, the comfort dividend arrives the same evening.
- Custom saving (advanced): enter your own gas-heated figure, for example from an EPC recommendation, when the presets do not fit.
- Heating fuel (advanced): electric heating pays the full electricity price for every lost kilowatt-hour, so the saving is scaled up by the current ratio of electricity to gas prices (about three times). Oil is treated like gas.
- Future energy price change (advanced): compounds each year's saving by the percentage you set, for the lifetime total.
- Professional installation payback (advanced): a professional whole-house job typically costs GBP 200 to GBP 400 and uses better materials, with payback still usually under four years.
- DIY cost including your time (advanced): adds your hours at whatever you value them, so the DIY-versus-professional comparison is fair. Self-adhesive EPDM rubber outlasts bargain foam on opening windows, and sash windows deserve their specialist brush-pile refurbishment.
- Total saved over the seals' life (advanced): every year's saving added up and shown net of materials. The one rule throughout: seal draughts, not ventilation. Leave trickle vents, air bricks and extractor fans alone, and never block the fixed vents serving open-flued gas fires, boilers and stoves, because carbon monoxide is the reason that rule is written plainly everywhere.
Savings basis: Energy Saving Trust.