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Blog Post 23 December 2021

How to draught-proof your windows and doors

Did you know that draught-proofing is one of the cheapest and most effective ways to save energy and money in your home?

By blocking up unwanted gaps around windows, doors and the floor that let the cold air in and warm air out, you’ll use less energy to heat your home this winter – which in turn will save your money on your energy bills.

Keep reading for our quick and simple advice on how to draught-proof your home this winter.


For windows that open, buy draught-proofing strips to stick around the window frame and fill the gap between the window and the frame. There are two types of draught-proofing strips:

  • Self-adhesive foam strips, which are cheap and easy to install, but may not last long.
  • Metal or plastic strips with brushes or wipers attached, which are long-lasting, but cost a little more.

Make sure the strip is the right size to fill the gap in your window. If the strip is too big, it will get crushed, and you may not be able to close the window. If it’s too small, there will still be a gap.

For sliding sash windows, it’s best to fit brush strips or consider getting a professional to carry out the work for you.

If your windows don’t open, use a silicone sealant. If you’re thinking of replacing your windows, consider installing energy efficient windows.

Worker putting rubber draught strip onto window indoors, closeup


Draught-proofing your front and back doors can stop a lot of heat from escaping. There are four main areas to consider draught-proofing:

  • Keyhole – buy a purpose-made cover that drops a metal disc over the keyhole.
  • Letterbox – use a letterbox flap or brush. You’ll need to measure your letterbox first to make sure you buy the right size.
  • Gap at the bottom – use a brush or hinged flap draught excluder.
  • Gaps around the edges – fit foam, brush or wiper strips like the ones we suggested above for windows.

Internal doors between two rooms only need draught-proofing if they lead to a room that you don’t normally heat during the winter months. Keep those doors closed to stop the cold air from moving into the rest of the house.

If there’s a gap at the bottom of the door, block it with a draught excluder – you can make one stuffed with used plastic bags or bits of spare material.


You can block gaps or cracks in your floor using filler. Floorboards and skirting boards often contract, expand or move slightly with everyday use, so you should use a filler that can cope with movement – these are usually silicone-based.

Look for flexible fillers, decorator’s caulk, or mastic-type products. Fillers come in different colours, and for indoor and outdoor use. They block gaps permanently so be careful when you apply them – wipe off any excess with a damp cloth before it dries. Fillers may break down over time, but they can easily be reapplied.


If you don’t use your fireplace, your chimney is probably a source of unnecessary draughts. Read our blog on how to draught-proof your chimney for more advice.

How much could you save?

Draught-proofing around windows and doors could save you around £30 a year (savings based on a typical gas-fuelled semi-detached home in Great Britain).

If you have an open chimney too, draught-proofing your chimney when you’re not using it could save an extra £20 a year in the same property type.

What’s more, draught-free homes are more comfortable at lower temperatures, so you may be able to turn down your thermostat by one or two degrees, saving even more on your energy bills!

Last updated: 21 December 2021