Draught-proofing room by room
Draughts get in wherever two parts of a house meet, or where something passes through a wall. Each guide below covers one part of the home: where the gaps are, the ways of sealing them, and what to watch out for.
If you’re not sure where your draughts are coming from, start with finding draughts. And before you seal anything, read what to leave open, as some gaps are there for a reason.
Chimneys and fireplaces
An unused chimney draws warm air out of the room day and night, and pulls cold air in through every other gap to replace it. Blocking it is usually the cheapest single job with the biggest saving. The guide compares the six main types of chimney draught excluder and explains which chimneys must never be blocked.
Read the chimney and fireplace guide · Which chimneys are safe to block
Doors and letterboxes
Outside doors leak round the frame, underneath, and through the letterbox and keyhole. Nearly all of it is DIY, and you’ll feel the difference the same evening. The guide covers seal types, the gap under the door, letterboxes, keyholes and cat flaps, and what to know about fire doors.
Read the door and letterbox guide
Windows
In older windows, most of the heat is lost through the gaps round the opening parts, not through the glass. Casement windows are easy to seal yourself; sash windows usually need a specialist. The guide also covers modern double-glazed windows, secondary glazing, shutters and curtains.
Read the window guide · Sash windows · Listed buildings and consent
Floors, lofts and other gaps
Gaps between floorboards and under skirtings, a loose loft hatch, and the holes made for pipes and cables all let in cold air. Most are quick fixes with cheap materials. The guide also explains how to deal with sockets and downlights safely.
Read the guide to floors, lofts and other gaps · Floors · Loft hatches · Pipes and cables
Where to start
If you’re doing it in stages, this order usually gives the most benefit for the least money:
- Block any chimney you don’t use.
- Seal round outside doors, and fit a letterbox brush.
- Seal round windows, starting with the rooms you use most.
- Fill gaps in floors and round the loft hatch, pipes and cables.
- Why draught-proofing matters: what causes draughts and what they cost
- Saving energy: other ways to make your home warmer
- Questions answered: short answers to common questions
- About this site: who runs it and how we keep the advice fair
Last checked 23 October 2026.