Draught Proofing

Draught proofing a building is an effective way to reduce energy use. Uncontrolled draughts let in too much cold air leading to wasted heat. Although ventilation is still needed as it helps to reduce condensation and damp.

Effective draught proofing seals up unwanted gaps that let cold air in and warm air out. This can be through doors, loft hatches, chimney flues, and window surrounds. Do not seal areas that are purposefully ventilated. Such as extractor fans, underfloor grilles or airbricks, wall vents or trickle vents.

The Energy Saving Trust website has general tips on draft proofing a property. Historic Environment Scotland have created specific guidance for draft proofing historic buildings.

Draught proofing is usually for external doors only. You may wish to draft proof between internal doors where there is significant difference in temperature variation between rooms. Fire doors or doors of special historical/heritage value shouldn’t be draught proofed.

For suitable doors you can:

• Draught proof around the door edge using fit foam, brush, or wiper strips.
• Draught proof around the letterbox using a flap or brush.
• Insulate the door itself. A thin layer of suitable insulation material can be added to the door’s panels.
• Cover keyholes with purpose made covers.

The GreenAge website has general tips on draft proofing doors. Historic England have created guidance for draft proofing windows and doors in historic buildings.

Lots of heat is lost through loft hatches. They let warm air escape or allow cold air in from the roof area. Especially if you have an insulated loft or roof space. Leaving a loft hatch uninsulated will make your loft insulation less effective.

Loft hatches which rest on the frame of the loft entrance can use a compression seal or foam strip around the lip edges. The seal should stop drafts when the hatch sits in place.

Hinged hatches that swing downwards should seal on the outside edge of the frame on top of loft hatch. Adding another strip on the inside of the hatch frame where the two strips meet creates a barrier to stop the draughts.

Insulating the top of the loft hatch stops heat loss through this space. This can be as simple as attaching insulation materials to the top of the hatch.

A chimney can be a large draw of warm air out of a room, even if it’s no longer used. The level of heat loss out a chimney can depend on a few things. The building height and the temperature outside can create the”stack effect”. To reduce this effect there are a few options you can take.

One affordable option is to put a draught excluder in the chimney. These block the flue to stop warm air escaping out and cold air being drawn down the chimney. These are often called chimney balloons or chimney sheep.

Installing a chimney cap or cowl, which covers the top of the chimney, can also stop excess air escaping. These also stop debris from nesting birds falling down the chimney.

The Energy Saving Trust have further guidance on draft proofing chimneys.