How Much Does Draught Proofing Cost in London? (2026 Prices)

Last updated: November 2026

When the heating goes on in November, many London homes start to show where the warm air is going: a cold stripe of air under the front door, a whistling letterbox, a rattling sash window that lets the curtains move on a windy night. Draught proofing is one of the cheapest ways to make a home feel warmer, and in older London housing it is often the first job worth doing before anything more expensive. This guide sets out what draught proofing costs in London in 2026, from a few pounds of DIY strip to a specialist sash window system, what a fair quote should include, how VAT works on it, what you can safely do yourself and where you must keep the ventilation your home needs.

TL;DR

Professional draught proofing for doors and casement windows costs around £200 to £250 nationally, according to Which?, and one 2026 London guide puts it at £250 to £500. DIY strips start at around £6. A dated London guide puts sash windows at £250 to £450 each for a fitted brush-pile system. Installed draught stripping is currently zero-rated for VAT.

What draught proofing costs in London in 2026

No regulator or trade body publishes a London price list for draught proofing, so most of the London figures below are market-observed from dated 2026 cost guides. The best independent anchor is Which?, whose guide (updated 6 October 2026) says "Hiring a professional installer to draughtproof your home could cost around £200", with around £250 for a professional whole-house installation in its cost table [1]. One provider's 2026 London price guide puts a whole property at £250 to £500 in London, against £200 to £400 elsewhere [2]. Sash windows are priced separately by specialists, and that is where London bills grow [3][4].

London prices from dated 2026 cost guides [2][3]; DIY prices and the national professional figure from Which? [1]. Treat these as typical quoted ranges, not fixed prices. VAT treatment differs between guides; see the VAT section below.

Two things explain most of the spread. The first is the type of window. Modern casement and uPVC windows take a stick-on or push-in seal in minutes, so a handyperson can do a whole house in a few hours. Timber sash windows, which are everywhere in Victorian and Edwardian London, need a specialist system routed into the sashes and frame, and usually some easing and adjusting so the window still opens smoothly, which is why one sash can cost more than every door in the house. The second is the condition of what is being sealed: a seal on a warped door or a rotten sash will not last, so a good quote often includes some repair first.

A worked example: a London Victorian terrace

For a typical London terrace with six to ten timber sash windows, the specialist figures above imply roughly £1,500 to £4,500 for brush-pile draught proofing alone, rising to about £2,100 to £5,500 if the cords and pulleys are overhauled at the same time. That is our arithmetic from one dated London and South East cost guide [3], not a published whole-house price, and some specialists discount for several windows in one visit. Add a few hundred pounds for the front and back doors, the letterbox, the loft hatch and any unused chimney. A national sash restoration guide dated May 2026 gives a similar per-window figure of £200 to £400 for draught proofing, with 2 to 4 hours of labour and £50 to £120 of materials per window [4].

What a fair draught proofing quote should include

A fair draught proofing quote, agreed before work starts, should state in writing:

• Every opening being treated: each external door, each window by type (casement, sash, uPVC), the letterbox, keyholes, the loft hatch, any unused chimney and any floors. "Draught proof the house" is not a scope.
• The product for each opening: stick-on foam or rubber, brush strip, a door weather bar, or a routed-in brush-pile system for sashes. Ask what lifespan the installer expects for each.
• Repairs as separate lines: easing a sticking door, re-cording a sash, replacing a parting bead or repairing rot. These are not draught stripping, and they affect VAT (see below).
• Making good: whether paint touch-ups after routing or planing are included, or left to you.
• Ventilation: confirmation that trickle vents, air bricks, extractor fans and any vents for fuel-burning appliances will be left clear.
• VAT: whether the price includes it and, if the installer is VAT-registered, that the draught-stripping part is zero-rated.
• Access and London costs: parking, any Congestion Charge, and whether upper-floor sashes can be done from inside.
• A guarantee: how long the installer stands behind the seals and the operation of the windows.
• Payment: a fixed price, with any deposit kept small. In our view, a strip job on doors and casements should not need a deposit at all.

The Consumer Rights Act 2015 requires a trader to "perform the service with reasonable care and skill" [15]. A written, itemised quote makes it far easier to hold anyone to that.

Costs by part of the house

External doors

The front door is often the single biggest draught in a London home. A brush or rubber strip around the frame closes the sides and top, and a brush strip or weather bar along the bottom closes the gap over the threshold. Which? puts a brush strip or weather bar "from around £6" [1]. Fitted by a professional, expect roughly £20 to £40 a door in London as part of a wider visit [2]. If the door is warped or drops on its hinges, it needs adjusting or planing first, which is a carpentry job; our guide to carpenter day rates in London explains how that is priced.

Letterboxes and keyholes

A letterbox brush or flap costs "under £10" and a keyhole cover "about £3", according to Which? [1]. Both are easy DIY jobs. Fitted, a letterbox seal is commonly £10 to £20 in London [2].

Casement and uPVC windows

Most casement windows can be sealed with self-adhesive foam, rubber or brush strips on the frame. Modern uPVC windows already have seals in the frame; if they are draughty, the gaskets may be worn or the hinges need adjusting, which a window repairer can often fix for less than replacement. Fitted strip costs roughly £20 to £40 a window in London [2].

Floorboards and skirting

Suspended timber floors, common in older London houses, can let cold air rise from the void below through gaps between boards and under the skirting. Filling those gaps is commonly priced at £60 to £120 a room in London [2]. Do not seal the air bricks in the outside walls that ventilate the void: they keep the timber below dry.

Loft hatches and unused chimneys

A compressible strip around the loft hatch costs little and stops warm air rising into a cold loft; fitted, it is commonly £15 to £35 [2]. An unused open chimney can be closed with a chimney draught excluder, which Which? says you can buy "from any good DIY store" [1]; fitted, expect around £20 to £45 in London [2]. Remove it before ever lighting a fire.

Sash windows: the London case

Draughty sash windows are a London problem more than a national one, because so much of the city's housing stock was built with them. A sash rattles and leaks air where the sashes meet, at the sides where they slide and at the top and bottom. Stick-on foam does not survive a sliding sash, so specialists fit a brush-pile seal into grooves routed into the sashes and the beads, then rehang and adjust the sashes so they still slide freely.

That is skilled joinery, which is why the price per window is high. A dated 2026 cost guide puts brush-pile draught proofing at £250 to £450 a window in London and the South East, £350 to £550 with the cords and pulleys overhauled, and £450 to £750 for a full overhaul [3]. The same guide tells readers to expect a premium of 20 to 30 per cent in London and the South East over the rest of the UK [3].

Before you compare quotes, it helps to know your three options:

• Draught proofing and overhaul: keeps the original windows, cuts draughts and rattles, and is usually the cheapest route for windows in fair condition.
• Secondary glazing: a separate inner pane, which adds more insulation and cuts noise. It costs more, and the original window then needs some ventilation of its own to avoid condensation between the panes, so ask the installer how they will handle that.
• Replacement windows: the most expensive option, and the only one of the three that falls under the building regulations (see below). In a listed building, or a conservation area, extra permissions may apply.

A specialist who mainly sells replacement windows has an incentive to tell you the sashes are beyond repair. Getting a second opinion from a sash repair specialist or an experienced carpenter is worth the time.

How VAT works on draught proofing

This is the most useful money point in this guide, and few quotes explain it. HMRC's VAT Notice 708/6 says: "A zero rate applies to the installation of certain specified energy-saving materials from 1 May 2023 to 31 March 2027" [5]. Draught stripping is one of those materials, defined as "strips that are fixed around windows, interior and exterior doors, and loft hatches to reduce draughts" [5]. The same notice says the rate will "revert to the reduced rate of VAT of 5%" from 1 April 2027 [5]. The notice was last updated in January 2024, so check the current position on GOV.UK before a large job.

In practice:

• If a VAT-registered business installs draught stripping in your home, that part of the job should not carry 20 per cent VAT before 1 April 2027.
• If you buy strips from a shop and fit them yourself, you pay the normal rate. The notice says "the sale of energy-saving materials by a retailer is always standard-rated" [5].
• Repairs are not draught stripping. Re-cording a sash, replacing timber or decorating are ordinary building work. Ask for the quote to show draught stripping and repair as separate lines so the VAT on each is clear.
• Many sole traders do not charge VAT at all because they are below the £90,000 registration threshold [6], so two honest quotes can differ for that reason alone.

We are not tax advisers. If the VAT on a large sash job looks wrong, ask the installer to explain which lines they have zero-rated and why.

What you can do yourself, and when to hire

Most draught proofing on doors, letterboxes, keyholes, casement windows and loft hatches is a reasonable DIY job if you can use a tape measure and a saw. Which? notes that how much DIY costs "depends on what you plan to draughtproof" [1], but the individual items are cheap.

Hire someone when:

• The windows are timber sashes. Routed brush-pile systems and rehanging sashes need joinery tools and experience.
• Doors or windows need adjusting, planing or repair first. A seal on a badly fitting door will not last.
• The floor void needs work. Lifting boards or filling large gaps is slower and messier than it looks.
• You live in a listed building. Get advice first (see below).
• Any room has a gas, oil or solid-fuel appliance. Ventilation for these appliances is a safety matter, not a comfort one.

A handyperson can usually do doors, casements, letterboxes and hatches in a single visit. Our guide to handyman hourly rates in London explains how London handypeople charge, including the minimum charge that applies to small jobs.

Is draught proofing worth it?

Which? says draught proofing your windows, doors and floors "could save you up to £55 in energy a year" [1]. On a typical house with doors and casement windows, a professional job at £250 to £500 would take roughly 5 to 9 years to repay at £55 a year, and a DIY job much less.

Sash windows are a different calculation. At several hundred pounds a window, energy savings alone will take a long time to repay the cost. The stronger reasons to do it are comfort, fewer cold spots, less rattling and noise from the street, and often a window that opens properly again. If the sashes need re-cording anyway, adding draught proofing in the same visit is usually better value than two separate jobs.

Draught proofing also works best alongside sensible heating control. Our guide to smart thermostat installation costs covers the next step, and if some rooms stay cold after the draughts are fixed, the problem may be the radiator itself; see why a radiator is not heating up.

Keep the ventilation: draught proofing, condensation and mould

Draught proofing stops the air you do not want; ventilation is the air you need. Which? is clear that "it's important not to completely seal your property. There needs to be some air flowing in and out" [1]. Its advice includes:

• "Don't seal kitchen and bathroom windows", because "the gaps will let out steam and reduce the risk of damp" [1]. Seal the inner doors to these rooms instead.
• "Make sure you keep outside ventilation in areas where there are open fires or flues" [1].

Never block trickle vents in window frames, air bricks, extractor fans, underfloor vents or vents serving a boiler, gas fire or stove. Government guidance on ventilation says rooms with open-flued appliances need "permanently open air vents to supply the air for combustion" [7]. If you have an open-flued gas appliance or a solid-fuel stove, we recommend asking a Gas Safe registered engineer (gas) or a qualified heating engineer (oil or solid fuel) to check the appliance and its ventilation after the draught proofing is done, and making sure there is a working carbon monoxide alarm in any room with a fuel-burning appliance.

Older London houses were built to rely on draughty windows, chimneys and air bricks for background ventilation. Seal them all without adding ventilation elsewhere and condensation can follow. Our guide to getting rid of damp and mould in London homes explains how to tell condensation from other kinds of damp.

Listed buildings, conservation areas and building regulations

Historic England publishes detailed guidance on draught-proofing windows and doors in older buildings [8]. In a listed building, the line that matters is how much historic fabric is changed. As a rule of thumb, removable stick-on strips are unlikely to need consent, while routing grooves into original sashes and frames alters the window and may need listed building consent. Speak to your borough's conservation officer before work starts on a listed home.

Draught proofing on its own is generally not treated as building work, but check with your local authority building control if it forms part of other work. Replacing windows is controlled: the Planning Portal says "Since 1 April 2002 building regulations have applied to all replacement glazing" [9], and the usual route is an installer registered with a competent person scheme such as FENSA or CERTASS [9][10]. That is one more reason to draught proof and repair sashes before deciding to replace them.

Grants and funded schemes in London

Government and Mayor-funded help exists for some homes, but it is narrow:

• Warm Homes: Local Grant in London lists draught proofing among the possible upgrades for privately owned homes with an Energy Performance Certificate (EPC) rating of D to G, usually where household income is £36,000 a year or less and savings are under £25,000 [11]. The Greater London Authority says it can "only fund measures that have been approved by your assessor", that demand is currently high, and that "Timber sash and case window replacement is excluded" [11].
• The Great British Insulation Scheme ended on 31 March 2026, and ECO4, the main energy-supplier scheme, is due to end on 31 December 2026 [12]. Do not plan a job around either.

Check eligibility on the official London application page before you commit, and be wary of anyone cold-calling to offer "free" draught proofing or insulation.

Why draught proofing costs more in London

London prices for the same job are commonly quoted 20 to 30 per cent above the rest of the UK [3]. The reasons are mostly overheads:

• Travel and vehicle charges. The Congestion Charge is £18 a day if paid on the day or in advance [13], and a non-compliant van pays the Ultra Low Emission Zone (ULEZ) charge of £12.50 a day, across all London boroughs [14].
• Parking. Many streets have permit-only parking, so a trader may need to pay for a bay or build parking time into the price.
• Access. Terraces with no rear access, upper-floor sashes and flats in mansion blocks all take longer.
• The housing stock. London has a high share of period timber windows, so more jobs need the expensive sash work rather than a quick strip.

Frequently asked questions

How much does it cost to draught proof a sash window in London?

One dated 2026 cost guide puts a specialist brush-pile draught proofing system at £250 to £450 per sash window in London and the South East. If the cords and pulleys are overhauled in the same visit, expect £350 to £550 a window, and £450 to £750 for a full overhaul. Some specialists discount for several windows in one visit.

Is draught proofing worth the money?

For doors, casement windows, letterboxes and loft hatches, usually yes: the materials are cheap and Which? estimates savings of up to £55 a year. For sash windows, energy savings alone repay the cost slowly, but the comfort, noise reduction and a window that works properly again are often worth it, especially alongside planned repairs.

Can I draught proof my own windows and doors?

Yes, for most doors, casement windows, letterboxes, keyholes and loft hatches. Brush strips, foam seals and letterbox brushes cost a few pounds each from a DIY store. Timber sash windows are better left to a specialist, because the seals are routed into the frame and the sashes need rehanging and adjusting so they still slide.

Does draught proofing cause damp or condensation?

It can if you seal everything. Homes need some fresh air to remove moisture from cooking, washing and breathing. Leave trickle vents, air bricks and extractor fans clear, do not seal kitchen or bathroom windows, and keep the ventilation that any gas, oil or solid-fuel appliance needs. Draught proofing done this way should not cause damp.

Is there VAT on draught proofing?

Installed draught stripping in homes is zero-rated for VAT from 1 May 2023 to 31 March 2027, after which the reduced 5 per cent rate applies. Strips you buy from a shop carry the standard rate. Repairs done at the same time, such as re-cording a sash, are not draught stripping, so ask for them as separate quote lines.

Do I need permission to draught proof a listed building?

Removable stick-on strips are unlikely to need consent, but routing grooves into original sash windows alters historic fabric and may need listed building consent. Draught proofing alone is generally not treated as building work, unlike replacement windows. If your home is listed, speak to your borough's conservation officer before any work starts.

Find a trusted local handyperson for draught proofing

Draught proofing is one of the cheapest ways to make a London home warmer this winter, and the difference between a seal that lasts and one that peels off in a month is usually the person who fits it. Loacally connects you with verified local tradespeople across London, from handypeople for doors and casements to carpenters for timber windows. Find a trusted local tradesperson near you, and read our guide on how to find a trusted tradesperson in London before you book.

Prices vary with the number and type of windows, their condition and access, so always get a written, itemised quote.

Sources

1. Which?. "How to draughtproof your home" (Adam Snook). 6 October 2026. https://www.which.co.uk/reviews/insulation/article/draught-proofing-aLi4N0F4P7VH (accessed November 2026)
2. Fantastic Services. "Draught proofing cost guide" (a home services provider's own 2026 price guide with a London column, used as market context only). 2026. https://www.fantasticservices.com/cost-guides/handyman/draught-proofing/ (accessed November 2026)
3. BestBuilders. "Sash window cost UK" (cost guide; London and South East ranges). Last updated 7 September 2026. https://www.bestbuilders.co.uk/costs/sash-window-cost-uk (accessed November 2026)
4. Trade2Base. "How to price sash window restoration in the UK." 27 May 2026. https://www.trade2base.com/blog/how-to-price-sash-window-restoration-uk (accessed November 2026)
5. HM Revenue and Customs. "VAT on energy-saving materials and heating equipment (VAT Notice 708/6)", sections 2.1, 2.3 and 2.9. Updated 31 January 2024. https://www.gov.uk/guidance/vat-on-energy-saving-materials-and-heating-equipment-notice-7086 (accessed November 2026)
6. GOV.UK. "Register for VAT." https://www.gov.uk/register-for-vat (accessed November 2026)
7. GOV.UK. "Approved Document F, volume 1: dwellings, frequently asked questions." 15 June 2022. https://www.gov.uk/guidance/approved-document-f-volume-1-dwellings-frequently-asked-questions (accessed November 2026)
8. Historic England. "Energy Efficiency and Historic Buildings: Draught-proofing Windows and Doors" (HEAG084). https://historicengland.org.uk/images-books/publications/eehb-draught-proofing-windows-doors/heag084-draughtproofing/ (accessed November 2026)
9. Planning Portal. "Doors and windows: building regulations." https://www.planningportal.co.uk/permission/common-projects/doors-and-windows/building-regulations/ (accessed November 2026)
10. GOV.UK. "Competent person scheme: current schemes and how schemes are authorised." Updated 17 September 2026. https://www.gov.uk/guidance/competent-person-scheme-current-schemes-and-how-schemes-are-authorised (accessed November 2026)
11. Greater London Authority. "Warm Homes: Local Grant in London." https://www.london.gov.uk/what-we-do/housing-and-land/improving-quality/warmer-homes (accessed November 2026)
12. GOV.UK. "Extending the ECO4 end date: government response." https://www.gov.uk/government/consultations/extending-the-eco4-end-date/outcome/extending-the-eco4-end-date-government-response-html (accessed November 2026)
13. Transport for London. "Congestion Charge." https://tfl.gov.uk/modes/driving/congestion-charge (accessed November 2026)
14. Transport for London. "Ultra Low Emission Zone." https://tfl.gov.uk/modes/driving/ultra-low-emission-zone (accessed November 2026)
15. legislation.gov.uk. "Consumer Rights Act 2015, section 49." https://www.legislation.gov.uk/ukpga/2015/15/section/49 (accessed November 2026)