Simple DIY draught-proofing

Keeping the cold air out

No-one likes to live in a draughty house. Apart from the discomfort, it’s a waste of money if the air that you have paid to warm up keeps escaping through gaps in the house and being replaced by cold air from outside.

Kathy Valentine

The good news is that draught proofing is easy. A bit of DIY can go a long way to plugging those gaps and keeping cosy at home. You’ll stop wasting money on your heating bills, and cut down on your carbon dioxide (CO2) emissions too. 

So, where do the draughts come from? Most houses, particularly old ones, have cracks and gaps through which warm air goes out and cold air blows in. Not all of these can be dealt with by a DIY-er, but many can, such as the gaps between or around floorboards; around windows and doors; through the letterbox; where pipework comes through external walls; around the loft hatch; and around electrical fittings. 

Mind the gap!

The most common draught-zones ... and DIY solutions to dealing with them:

  • Windows: Use foam, metal or plastic draught strips, or brush seals for sash windows. Temporary secondary glazing is another option.
  • Exterior doors: Fit brush or hinged-flap draught excluders, fitted along the bottom of the doors.
  • Interior doors: Cut draughts with ‘snake’ draught excluders, brushes or similar strips of material.
  • Unused chimneys: Chimney draught excluders – often known as ‘chimney balloons’ – are available from most DIY stores. Remember to remove them in summer to let the air circulate.
  • Around pipework: Apply silicone mastic, wall-filler or expanding foam as appropriate.
  • Floorboards and skirting boards: Fill the gaps with flexible fillers, clear or brown silicone mastic, decorators’ caulk or similar products.
  • Cracks in walls: Use cement or a hard-setting decorators’ wall-filler.
  • Redundant extractor fan outlets: These should be blocked up.
  • Loft hatches: Use strips of draught excluding material fitted around the edges of the frame, and don’t forget to insulate the hatch itself.
  • Lighting and electrical fittings: Plug the gaps around the fittings with wall-filler. Letterboxes: Fit flaps or brushes to keep the cold air out and the warm air in. See over for instructions