Gaps around doors, windows, floorboards and letterboxes let cold air in and warm air out all winter long, quietly pushing up heating bills without most homeowners realising just how much is being lost. Draughts around doors and windows alone can add a significant amount to winter heating costs, yet draught-proofing is one of the cheapest and most effective home improvements available, often paying for itself within a single heating season.
This guide covers where draughts typically come from, how to find them, and the most effective ways to seal them yourself.
Why Draught-Proofing Matters
In short: a draughty home forces your heating system to work harder to maintain the same temperature, wasting energy and money in the process. Sealing common draught points is one of the highest-value, lowest-cost improvements a UK homeowner can make, particularly in older properties with original doors, windows and floorboards.
How to Find Draughts in Your Home
- On a cold, windy day, hold the back of your hand near window and door frames, skirting boards, and letterboxes to feel for moving air.
- Light a candle or incense stick and watch for flickering near likely draught points, an old but reliable trick for spotting airflow you cannot otherwise feel.
- Check for daylight visible around door frames when the door is closed, which usually signals a gap worth sealing.
Common Draught Points and How to Fix Them
External Doors
A door sweep or brush strip fitted to the bottom of the door closes the gap between the door and the floor, while self-adhesive foam or rubber strip around the frame seals the sides and top. Letterboxes benefit from a dedicated letterbox brush or flap cover, since an unsealed letterbox is a surprisingly large source of heat loss.
Windows
Self-adhesive foam strip is the simplest fix for gaps around window frames, particularly on older timber sash windows, which are notoriously draughty. Silicone sealant can close small gaps in the frame itself, while heavier curtains or thermal linings add an extra layer of insulation once the draught itself has been dealt with.
Floorboards and Skirting Boards
Gaps between floorboards, common in older properties with suspended timber floors, can be filled with a flexible decorator’s filler designed for this purpose, or covered with a well-fitted underlay and carpet. Gaps where skirting boards meet the floor can be sealed with a paintable acrylic sealant.
Loft Hatches
Loft hatches are often overlooked, but an unsealed hatch allows warm air to escape directly into an unheated loft space. Foam draught strip around the hatch frame, combined with an insulated hatch cover, closes this gap effectively.
Chimneys and Unused Fireplaces
An open, unused chimney can be one of the single biggest sources of draughts in a home. A chimney draught excluder, sometimes called a chimney balloon or pillow, blocks the flow of cold air while still allowing the chimney to be used again if needed later.
Cost of Draught-Proofing a UK Home
| Job | Typical DIY Cost |
|---|---|
| Door and window foam strip | £5 to £15 per roll |
| Door sweep or brush strip | £8 to £20 per door |
| Letterbox brush or flap | £10 to £20 |
| Chimney draught excluder | £15 to £35 |
| Loft hatch insulation cover | £15 to £30 |
| Silicone sealant and filler | £5 to £10 per tube |
Compared with major insulation work, draught-proofing is one of the most affordable ways to make a noticeable difference to how a home feels and how much it costs to heat.
Balancing Draught-Proofing with Ventilation
While sealing unwanted gaps is worthwhile, homes still need a degree of ventilation to prevent condensation and damp building up indoors. Trickle vents on windows, extractor fans in kitchens and bathrooms, and airbricks serving suspended floors should be left clear even after draught-proofing the rest of the home.
Frequently Asked Questions
How much can draught-proofing save on heating bills?
Savings vary by property, but draught-proofing is consistently rated as one of the most cost-effective home energy improvements available, often paying for the materials within a single winter through reduced heating use.
Is draught-proofing something I can do myself?
Yes. Most draught-proofing products, including foam strip, door sweeps and letterbox brushes, are designed for straightforward DIY installation with no specialist tools required.
Can a house be too draught-proofed?
It is possible to over-seal a home if ventilation is neglected at the same time, which can lead to condensation and damp problems. Trickle vents, extractor fans and any required airbricks should always be left clear.
Where should I start if my whole house feels draughty?
Start with external doors and windows, since these are usually the biggest and easiest sources of draughts to fix, before moving on to less obvious areas such as loft hatches and unused chimneys.
Related Reading
- Eco-Friendly Solutions for Fixing Leaks and Conserving Water
- Loft Vacuuming: Benefits, Costs and Hiring Tips
About the author: This guide was written by the Routen House editorial team.