Draught proofing your home to maximise savings

Understanding Draught Proofing and Why It Matters for Your Home

Every winter, millions of UK homes quietly haemorrhage heat through gaps and cracks that their owners have never noticed — gaps around door frames, between floorboards, beneath skirting boards, and up open chimney flues. These unintentional openings cost real money every single month that the heating is running, and fixing them is often surprisingly simple and inexpensive.

Draught proofing is the process of identifying and sealing unintentional gaps and cracks in your home’s structure — the kind that allow cold outside air to creep in and warm inside air to escape. It is distinct from deliberate, healthy ventilation such as trickle vents, extractor fans, and air bricks, which your home genuinely needs to prevent condensation and damp. For most UK homeowners, draught proofing is one of the cheapest and fastest-payback improvements available, with many individual measures costing under £20 and taking no more than an afternoon to fit yourself.

It is critical to understand the difference between “bad” draughts and “good” ventilation before you reach for the sealant. Bad draughts are uncontrolled — gaps around door frames, cracks between floorboards, open chimney flues, and poorly fitted letterboxes. Good ventilation is intentional and controlled — it allows moisture-laden air from cooking, showering, and breathing to escape the building before it condenses on cold surfaces and causes mould. Sealing your trickle vents shut or blocking an extractor fan outlet would be a mistake; sealing the gap where your skirting board meets a draughty floor void is an excellent idea. According to the Energy Saving Trust, draughts account for a significant proportion of heat loss in older UK homes — particularly pre-1920 solid-walled Victorian and Edwardian properties with suspended timber floors and sash windows, where multiple draught sources often exist simultaneously.

Practical tip — before buying anything, walk slowly around your home on a cold, windy day and note every place where you can feel cold air movement. This simple list will guide everything you do next.

How Much Can Draught Proofing Actually Save You

Professionally draught proofing your windows and doors could save a typical semi-detached home in the region of £45 to £65 per year on energy bills, according to Energy Saving Trust guidance — but savings vary considerably depending on your property’s age, size, and how leaky it currently is.

Those figures represent the conservative end of what is achievable. For an older, detached property with an open fireplace, original sash windows, suspended timber floors, and a loft hatch that has never been draught-sealed, the combined savings from a thorough whole-home approach can be meaningfully higher. The exact figure depends on how your home was built, what fuel you use for heating, and how many hours a day the heating runs — so treat published estimates as a useful benchmark rather than a guarantee.

What matters just as much as the direct saving is the amplifying effect draught proofing has on other insulation measures. If you have already invested in loft insulation or cavity wall insulation, uncontrolled draughts partially undermine that investment by allowing cold air to circulate at floor level and through gaps in the building fabric. Draught proofing should be thought of as the foundation layer of any whole-home energy efficiency plan — it makes every other measure work harder. whole-home insulation guide

With Ofgem‘s energy price cap keeping UK energy costs elevated in 2026, even modest reductions in heat loss translate into real money over a full heating season. A £25 door seal that reduces your gas consumption slightly every single day from October to March pays for itself quickly — and keeps paying back year after year with no further investment.

Practical tip — calculate your potential saving by checking the Energy Saving Trust’s online savings calculator, which allows you to input your property type and fuel tariff for a more personalised estimate.

Where Heat Escapes First — Prioritising the Biggest Draughts

Not all gaps are equal, and approaching draught proofing in a logical priority order means you get the biggest savings earliest, even if you tackle the work gradually over several weekends.

The simplest DIY draught audit requires no special equipment. On a cold, windy day, hold a lit incense stick near suspected gaps — any movement in the smoke reveals air infiltration. Alternatively, dampen the back of your hand slightly and move it slowly around door and window frames; you will feel cold air immediately. On a sunny day, a thin strip of light visible under an external door or around a window frame is a reliable sign of a significant gap. Take a photograph and note the location — you are building your action list.

For most UK homes, the priority order looks like this:

1. Chimneys and fireplaces — an open chimney flue is essentially a permanent hole in your ceiling, and it is often the single largest source of heat loss in older homes.
2. External doors — threshold gaps, letterboxes, and poorly fitted frame seals are collectively significant, particularly on older wooden doors that have warped over time.
3. Windows — sash windows in period properties are especially problematic and require specific solutions rather than generic foam strips.
4. Suspended timber floors and skirting boards — cold air enters the floor void through air bricks and travels up through every gap between boards into the living space above.
5. Loft hatches — rarely insulated and rarely sealed, yet positioned directly above the warmest air in the house.
6. Pipework and electrical socket penetrations on external walls — individually small, but collectively worth addressing once the major sources are dealt with.

Properties built before 1919 are particularly likely to have all six categories of draught source present at once, making a systematic room-by-room check worthwhile. older home energy efficiency guide

Practical tip — photograph each draught source you find before you seal it, so you can track what you have completed and demonstrate progress to anyone helping you or checking the work.

Draught Proofing External Doors — Products, Costs and What to Buy

External doors are one of the highest-impact areas to address, and the range of products available makes it easy to match a solution to your budget, your door type, and your DIY confidence level.

Every external door has three key areas that need attention. The threshold is the bottom edge of the door — the gap between the door base and the floor. The frame surround covers the sides and top, where the door closes against the frame. And the fittings — letterbox, keyhole, and sometimes a cat flap — are individual penetrations that are easy to overlook.

Threshold Excluders and Door Bottom Seals

A gap under an external door can be surprisingly large — enough to let in a noticeable cold breeze and lose meaningful warmth. The options range from simple fabric draught excluders placed on the floor against the door (inexpensive but moved every time the door opens) to fixed mechanical solutions. Brush strips and rubber seal strips are screwed directly to the bottom of the door and move with it; they cost from around £8 to £20. Automatic door seals are the most elegant solution — they drop down when the door closes and lift clear when it opens, so they never impede movement. These cost £25 to £40 for a quality version and take under an hour to fit.

Frame Draught Excluders

Self-adhesive foam compression strips are the cheapest frame solution, costing £3 to £8 for a full door set, but they compress permanently within a season or two and need replacing. Rubber or silicone compression seals last considerably longer, cost £10 to £20, and give a better seal against an uneven frame. For timber doors that have warped or where the fit is poor, it may be worth having the door rehung or planed before applying any seal — otherwise you are wasting your money.

Letterboxes, Keyholes and Flap Covers

A standard letterbox is a direct hole through your front door, and its draught contribution is often underestimated. A brush insert or a cover plate with an internal flap costs £5 to £15 and takes minutes to fit. Keyhole covers — small rotating or sprung plates — add a further marginal improvement for £2 to £5. Neither is transformational on its own, but both form part of a properly sealed door and should not be skipped.

Practical tip — when buying compression seal strips, take a measurement of your door frame and check the product dimensions carefully. Many strips are sold in standard lengths that may not cover a full door surround in a single pack.

Draught Proofing Windows — Sash, Casement and Beyond

Windows are the second major target for draught proofing, and the right approach depends entirely on which type of window your home has.

The two most common window types in UK homes are casement windows, which hinge outward or inward on a side or top-hung mechanism, and sash windows, which slide vertically in a frame and are found extensively in Victorian, Edwardian, and Georgian period properties. Sash windows are significantly harder to seal effectively because the sliding mechanism means you cannot simply apply a compression strip around the whole frame without blocking the window’s movement.

Casement Windows

Self-adhesive rubber or foam compression strips pressed into the rebate — the channel the window closes into — are effective and cost approximately £5 to £15 per window depending on size. For timber-framed casement windows where the glazing putty has cracked and shrunk away from the glass edge, a careful application of clear silicone sealant around the glass perimeter closes another common leak point. Clean the surface thoroughly before applying any sealant to ensure adhesion.

Sash Windows

Purpose-made sash window draught proofing kits use brush pile strips — fine bristle seals set into routed channels in the sash frame — that allow the window to slide freely whilst maintaining a seal along the meeting rail and sides. Having this done professionally typically costs £50 to £150 per window, and DIY kits are available for £20 to £50 if you are comfortable with basic woodworking. A sash stop, which holds the lower sash firmly shut at its closed position, adds a further layer of sealing for windows used infrequently.

Secondary Glazing for Period Homes

Secondary glazing — a separate internal pane fitted inside the existing window — is worth a mention for period homes where conservation area rules or listed building status prevent full window replacement. It is not strictly a draught proofing measure in isolation, but it significantly reduces both heat loss and cold air infiltration through a single sash window for a cost of roughly £150 to £400 per window. secondary glazing guide for period properties

Practical tip — if you live in a conservation area and want to draught proof or replace original sash windows, contact your local planning authority before starting work. Some interventions are permitted development; others require prior consent.

Tackling Chimneys and Fireplaces — the Biggest Hidden Draught

An open chimney flue is one of the most significant sources of heat loss in any home that has one, because warm air rises continuously through the flue and pulls cold replacement air in at lower levels throughout the house — even when no fire has been lit for months.

The physics here are straightforward. Warm air is less dense than cold air, so it naturally rises. Your chimney provides a direct, unobstructed path from the warmth of your living room to the cold outside. Even on a calm day, the stack effect means heat is being pulled upwards. On a windy day, the loss is considerably greater.

Chimney Balloons

A chimney balloon is an inflatable cushion — typically made from a tough laminate material — that is inserted into the flue just above the fireplace opening and inflated to create a tight seal against the flue walls. They cost around £20 to £30, take a few minutes to fit, and are easily removed and deflated for storage when you want to use the fireplace. The single most important safety rule is this: always attach the provided warning tag visibly inside the fireplace, reminding anyone in the household to remove the balloon before lighting a fire. Lighting a fire with a chimney balloon in place is dangerous and must be avoided.

Chimney Sheep

Chimney sheep are a British-made alternative using compressed natural wool formed into a plug that is pushed into the flue. They perform a similar function to a balloon at a similar price point, with the added appeal of a natural, reusable material. The wool also absorbs a degree of moisture, which some homeowners find beneficial in preventing any slight damp from condensation within the flue.

Capping Disused Chimneys

For a chimney that is permanently out of use, a purpose-fitted cowl or cap installed at the chimney pot by a professional provides a more permanent solution. Critically, a properly specified cap retains some ventilation — completely sealing a chimney with no airflow can cause the flue to become damp, which damages the lining and can lead to staining on internal walls. The cost of a professionally capped chimney runs from approximately £100 to £250 including labour, depending on the height and accessibility of the stack. chimney maintenance and draught proofing

Practical tip — never seal a chimney that serves a gas appliance, solid fuel stove, or any combustion appliance. Only flues that are genuinely disused and confirmed free of any live appliances should be sealed, and even then, some ventilation must be retained.

Floors, Skirting Boards and Internal Gaps — Often Overlooked Savings

Suspended timber floors are found in the vast majority of UK homes built before 1919, and they represent a draught source that most homeowners never address — yet the potential savings are real.

A suspended timber floor sits above a ventilated void between the ground and the underside of the floorboards. The void is ventilated intentionally through air bricks in the external walls, to keep the timber dry and prevent rot. The problem is that the air moving through that void finds its way into the room above through every gap between the floorboards and around the edges of the floor where it meets the skirting boards. In a room with original wide-plank floorboards, the draught coming through the floor on a cold day can be noticeable even when standing several metres from the external wall.

Filling Floorboard Gaps

For narrow gaps between boards, flexible decorator’s caulk or a purpose-made wood floor gap filler pressed in with a finger or putty knife is an effective and inexpensive fix. The flexibility of these products is important — timber moves seasonally as it absorbs and releases moisture, so a rigid filler will crack and fall out. For wider gaps, thin slivers of timber cut to fit, glued, and tapped gently into the gap provide a more durable result. A tube of flexible filler costs £3 to £8 and covers a considerable run of gaps.

Skirting Board Sealing

Cold air travels from the floor void up behind the skirting board and into the room through the joint between the skirting and the floorboards, and through the joint between the skirting and the wall. A thin, continuous bead of flexible sealant along both of these joints closes the path for a materials cost of under £5. This is a half-hour job that can make a noticeable difference to floor-level comfort in older rooms.

Pipework Penetrations and Electrical Sockets

Where water pipes, boiler flues, or cables enter through external walls, the gaps around them are often larger than they appear and can allow cold air to travel directly from outside. Fire-rated expanding foam sealant is the correct product for most pipework gaps — ordinary expanding foam is not suitable where a fire rating is required. Acoustic sealant can be used for cable entries. Electrical back-boxes on external walls are a surprisingly effective draught pathway; draught-proof pads designed to fit inside the back-box behind the socket plate are available from DIY retailers for a few pence each and take seconds to fit. home energy audit checklist

Practical tip — do not block the air bricks themselves when sealing a suspended floor. These bricks ventilate the floor void and protect the timber structure beneath. Seal the floor surface above, not the ventilation that serves it.

Loft Hatches and Internal Doors — Quick Wins You May Be Missing

Loft hatches and internal doors are among the most frequently overlooked draught proofing opportunities in UK homes, yet both can be addressed quickly and inexpensively.

Your loft hatch sits at the top of your home’s warm zone and opens directly into the coldest part of the building — the unheated loft space above. Most loft hatches are a thin piece of plywood or MDF with no insulation and no draught seal, which means warm air rises freely into the loft every time there is any air movement. Fitting a draught strip around the hatch frame — the same compression seal used on a door — costs under £10 and takes fifteen minutes. Adding an insulated loft hatch cover on top of the hatch, or fixing a rigid insulation board to the upper face of the hatch itself, addresses the heat conduction problem as well as the draught. Purpose-made insulated loft hatch covers are available for £20 to £50 and are straightforward to fit. loft insulation guide for UK homes

Internal Doors

Internal doors matter for draught proofing in a different way to external doors. They do not seal the building envelope directly, but they control the flow of warm air between heated and unheated spaces within the home. Keeping internal doors to unheated hallways, utility rooms, and garages closed and reasonably well fitted prevents warm air from your living areas being drawn towards the coldest parts of the house and lost.

A simple fabric draught excluder placed at the base of an internal door to an unheated room — or a draught lobby created by keeping a hall door closed — can reduce the heating demand on adjacent rooms noticeably. If you have a radiator in a hallway, consider whether that hallway really needs to be heated, or whether closing the door between the hall and the main living space would be more efficient.

Should You Hire a Professional

The majority of draught proofing work is well within the capabilities of a confident DIYer with basic tools and an afternoon to spare. However, for sash window work involving routing channels, chimney capping at height, or identifying complex draught pathways in an older property, a professional draught proofing assessment and installation is worthwhile. Look for a tradesperson registered with TrustMark — the government-endorsed quality scheme for home improvement work — which you can verify at the TrustMark official register online. For any work that qualifies under funded schemes, TrustMark registration is typically a requirement for the work to be eligible.

According to the Energy Saving Trust, a home that is properly draught proofed uses its heating system more efficiently — meaning your boiler or heat pump runs for shorter periods to maintain the same indoor temperature. This compounds the direct saving from reduced heat loss into a broader improvement in your home’s overall energy performance.

Practical tip — if your home has a cavity wall, a draught proofed loft, and a modern boiler but still feels cold and draughty at floor level, suspended floors and the loft hatch are almost certainly contributing to the problem. Address these two areas before concluding that more expensive work is needed.

Grants and Financial Support for Draught Proofing in 2026

Draught proofing is inexpensive enough that most homeowners can fund it from their own pocket without difficulty — but it is worth knowing what support is available, particularly for households on lower incomes or those with older, inefficient homes.

The Great British Insulation Scheme, administered by Ofgem in 2026, provides funding for insulation improvements in less energy-efficient homes across England, with separate but equivalent schemes operating in Scotland, Wales, and Northern Ireland. Draught proofing may be included as part of a broader package of measures under this scheme, though the primary focus is on cavity wall and loft insulation. Eligibility is assessed based on your home’s Energy Performance Certificate rating and, in some cases, your household income. Contacting your energy supplier is the simplest first step, as most major suppliers participate in scheme delivery.

The ECO4 scheme — the government’s Energy Company Obligation programme — similarly funds energy efficiency improvements for eligible households, with a focus on homes that score poorly on their EPC and are occupied by households receiving certain means-tested benefits. If you believe you may qualify, your energy supplier can assess eligibility directly. ECO4 scheme explained for UK homeowners

For the majority of homeowners who do not qualify for funded schemes, the straightforward cost-benefit case for DIY draught proofing is compelling on its own terms. Spending £50 to £100 on a comprehensive draught proofing of an older semi-detached home — covering the door seals, window strips, chimney balloon, floor gaps, and loft hatch — is likely to pay back in energy savings within a single heating season. Every year thereafter is pure saving.

Practical tip — always get at least three quotes if you are having professional draught proofing carried out, and ask each tradesperson to explain which areas they intend to address and why. This will vary based on your home’s specific construction, so a quote based on a proper survey of your property is far more reliable than a standard rate quoted over the phone.

Putting It All Together — A Room-by-Room Draught Proofing Plan

The most effective approach to draught proofing your home is systematic. Rushing straight to the products without a clear audit first is the most common mistake — it results in money spent on minor gaps while the major heat losses continue unchecked.

Here is a practical sequence that works well for most UK homes:

1. Carry out a whole-home draught audit on a cold, windy day using an incense stick or damp hand test. Walk every external wall, every window, every door, every area of floor, and note what you find.
2. Address the chimney first if you have an open or disused fireplace. Fit a chimney balloon or chimney sheep and note it clearly as the largest single intervention available to you.
3. Move to the external doors — fit a quality threshold seal, compression strips to the frame, and a brush insert to the letterbox. This is a morning’s work for the whole house.
4. Address windows by type — compression strips for casements, professional or DIY brush pile kit for sash windows.
5. Tackle the floors — fill floorboard gaps with flexible filler, seal the skirting board joints with caulk, and check for obvious pipework gaps near the floor.
6. Fit draught seals and insulation to the loft hatch.
7. Finish with the small penetrations — back-box pads, cable entries, and any remaining pipework gaps on external walls.

This sequence ensures that you address the highest-impact areas first and work methodically towards the smaller gains. In a typical three-bedroom semi-detached home with a mixture of casement and sash windows and a disused fireplace, completing all seven stages might take two or three weekends and cost between £80 and £180 in materials — depending on how many windows need specialist treatment.

It is also worth revisiting your draught proofing every two or three years. Foam compression strips degrade with seasonal temperature changes. Silicone sealant can crack where two different materials move at different rates. A chimney balloon needs checking to ensure it has not deflated or slipped. This is not a one-time task but a simple, low-effort maintenance habit that keeps your home comfortable and efficient year after year.

Practical tip — once you have completed your draught proofing, check your home’s Energy Performance Certificate rating. If significant improvements have been made, it may be worth having a new EPC assessment carried out — an improved rating can benefit your home’s value and mortgage eligibility, and may affect your eligibility for certain grant schemes.