Draught-proofing: stop draughts without blocking ventilation

Who this is useful for

• Homes with noticeable draughts around doors, windows, letterboxes, keyholes, loft hatches, floorboards, skirting boards or an unused chimney.
• Renters looking for low-cost, often removable measures. Check your tenancy agreement first.

What to check first

Never block these:

• trickle vents in window frames, air bricks, wall vents and ventilation grilles
• extractor fans and their outlets
• vents serving a gas fire, boiler, cooker, solid-fuel stove or oil appliance

Energy Saving Trust warns that flueless and open-flued appliances need ventilation to work safely. If you have one, ask a registered engineer before reducing airflow in that room.

Also check:

• Existing damp or mould. Sort out ventilation and the cause of the damp before sealing gaps.
• Where the draughts are. On a windy day, feel around frames, hatches and floors with the back of your hand.

Practical next steps

• Doors: fit brush or compression strips, a letterbox flap or brush, and keyhole covers. Use a draught excluder along the bottom of internal doors to unheated rooms.
• Windows: fit strips to opening windows. Seal fixed gaps between the frame and the wall with a suitable sealant.
• Floorboards and skirting: fill gaps with a flexible filler or sealant. If you have a suspended timber floor, keep the air bricks outside clear so the space underneath stays dry.
• Loft hatch: fit draught strips and insulate the hatch.
• Chimney: use a chimney draught excluder that does not block it completely, and remove it before lighting a fire. A chimney can also be capped professionally, with ventilation kept.
• Pipes and cables: seal gaps where they pass through walls, floors and ceilings.

Ventilation and moisture afterwards

Cooking, showering, drying clothes and breathing all add moisture to the air. Once draughts are sealed, that moisture needs a planned way out:

• use extractor fans while cooking and showering, and for a while afterwards
• keep trickle vents open
• dry clothes outdoors where possible, or in a ventilated room

Persistent condensation, mould or stuffy air are signs that your home needs more controlled ventilation, not less.

Important limitations

• How much you save depends on how draughty your home is now. We do not give a single figure.
• Older, listed or historic buildings may need specialist advice, particularly for original windows and doors.
• Draught-proofing does not replace insulation, and insulation does not replace ventilation.

Grants and support

Help depends on where you live, your income and your home. Check the official service for your nation, and never pay anyone to “unlock” a government grant.

• England: the Warm Homes: Local Grant is run through councils for lower-income households in homes with an EPC rating of D to G. Availability varies by council.
• Great Britain: the Energy Company Obligation (ECO4) runs until 31 December 2026. Whether a supplier will take a new application depends on its delivery plans. The Great British Insulation Scheme closed on 31 March 2026.
• Scotland: Warmer Homes Scotland, through Home Energy Scotland.
• Wales: Nest, through the Welsh Government.
• Northern Ireland: the Affordable Warmth Scheme, through the Housing Executive.

See current help and grants for more detail.

Related tools and guides

• Loft insulation
• Heating controls and boiler flow temperature
• Ventilation, condensation and damp
• Energy bill calculator

Sources

• Energy Saving Trust: draught-proofing
• Energy Saving Trust: how to draught-proof your chimney
• Energy Saving Trust: damp and condensation
• GOV.UK: Warm Homes: Local Grant
• Ofgem: Energy Company Obligation
• Ofgem: Great British Insulation Scheme
• Home Energy Scotland: Warmer Homes Scotland
• Welsh Government: Nest eligibility
• Housing Executive: Affordable Warmth Scheme

Official sources checked 2 October 2026.