Double glazing quotes in London
Compare free written quotes from local installers who cover your London postcode, for replacement windows, timber sashes, secondary glazing, acoustic glass and repairs. In London, your lease, your borough and your flight path decide what you can fit.
52.6% of London households live in flats. Get the freeholder's consent first.
- Installers you asked for, not a salesperson at the door
- Local installers who cover your postcode survey and quote in writing
- Free and no obligation. Say no to every quote if none suit you
We are a free quote-matching service, not an installer.
How it works
How London double glazing quotes reach you
You choose to be contacted. Nobody knocks on your door.
Tell us the job
Seven questions: property type, window count, frame material, timing, ownership, postcode and contact details.
One confirmation call
A short call confirms the details, then local installers who cover your postcode get in touch.
Quotes in writing
Each installer surveys and quotes in writing. Mention your lease, conservation area or airport scheme.
Jobs installers quote for
What you can get quoted for in London
London installers quote for replacement windows, secondary glazing, glass-only sealed unit replacement and repairs.
- Timber or heritage sash windows for inner London's pre-1919 streets and Article 4 conservation areas.
- Secondary glazing for listed homes and homes inside the Heathrow scheme.
- Acoustic laminated glass under the Heathrow and London City flight paths.
- New sealed units and repairs where the frames are sound and only the glass or hardware has failed.
Ask the installer whether a front or back door can go on the same quote.
Get London window quotesFree, no obligation
Boroughs
Double glazing in outer London boroughs
Five outer London areas have their own page, because each council sets its own window rules street by street:
- Double glazing quotes in Enfield (EN1, EN2)
- Double glazing quotes in Barnet (EN5, N20)
- Double glazing quotes in Bromley, where the Chancery Lane (Beckenham) direction controls windows
- Double glazing quotes in Romford, home of Havering's Gidea Park Article 4 direction
- Double glazing quotes in Ilford, near Redbridge's Aldersbrook and Lake House direction
Local factors
What changes a London double glazing quote
Six things change a London quote: flat or house, conservation area or Article 4 direction, listed status, the age of the home, flight path and renting. Each one changes the product, the paperwork or who pays, so tell installers which apply before they survey.
| In London | What it changes in your quote | Ask or check |
|---|---|---|
| 52.6% of households in flatsCensus 2021 | Freeholder consent, and often planning permission | Written consent and the specification, before quotes |
| More than 1,100 conservation area recordsplanning.data.gov.uk | Matching style, often timber, and sometimes an application | Whether the installer prepares the application |
| 19,286 listed building entriesHistoric England | Listed building consent before any change | Repair or secondary glazing for the old windows |
| 39.9% of inner London properties built before 1919VOA 2025 | Sashes to refurbish, secondary glaze or replace | Whether they overhaul box sashes as well as replace them |
| Up to 100% of eligible costs inside Heathrow's noise boundaryHeathrow | An airport scheme may pay for the windows | The airport's postcode checker, before you pay yourself |
| 30.0% of households rent privatelyCensus 2021 | Landlords must reach EPC band C on all tenancies by 1 October 2030 | The U-value of each window, in writing |
Double glazing quotes for London flats: consent first
Most London window jobs start with the freeholder or managing agent, not the installer. 52.6% of London households live in flats, against 21.4% across England (Census 2021, TS044).
Flats do not have householder permitted development rights, so a change of appearance can need planning permission. The Planning Portal adds that "if you are a leaseholder, you may first need to get permission from your landlord or management company".
- Read your lease to see who owns the windows.
- Get written consent and the specification: colour, opening style and glazing bars.
- Tell installers the floor level, since access above the first floor changes the job.
Our guide to replacing windows in a leasehold flat explains licences for alterations and who pays.
Get quotes for a London flatFree, no obligation
Window quotes in London conservation areas and Article 4 boroughs
Conservation areas cover much of London: its 33 councils have published more than 1,100 conservation area records to the national planning data platform, led by Richmond (85), Lambeth (65), Tower Hamlets (61), Westminster (56) and Southwark (56). Some boroughs add Article 4 directions that remove the right to change windows without permission:
| Borough | What the council says about windows |
|---|---|
| Kensington and Chelsea | Conservation area directions control "changing windows, front doors", street by street. |
| Hackney | The De Beauvoir direction (confirmed 27 November 2008) requires permission for "changes to windows"; further directions cover Beck Road, Brownswood and St Mark's. |
| Islington | Article 4(2) directions cover "changing external doors and windows or painting brickwork". |
| Hounslow | In Bedford Park and Gunnersbury Park Article 4 streets, replacing windows "will usually require Planning Permission"; PVCu and aluminium are "not usually considered appropriate". |
| Richmond upon Thames | Article 4 directions in 42 of 85 conservation areas need permission for new windows; "plastic looking windows" are "not likely to be acceptable" in place of timber. |
Check your borough's conservation map, then ask installers whether they prepare the application.
Get conservation area window quotesFree, no obligation
Acoustic glazing quotes under the Heathrow and London City flight paths
Heathrow's Residential Insulation Scheme funds up to 100% of eligible costs, including "replacement primary windows or secondary glazing and external doors", for homes inside its noise boundary. The indicative map covers places such as Cranford, Heston, Longford, Sipson and Harlington. London City Airport runs its own Sound Insulation Scheme, with three tiers by noise level.
Run the airport's postcode checker before you pay for windows yourself. Outside the boundary, ask installers to quote acoustic laminated glass and state its sound reduction (Rw) figure.
Get acoustic glass quotesFree, no obligation
Window quotes for London landlords: EPC C by 1 October 2030
30.0% of London households rent privately, against 20.5% across England (Census 2021, TS054). Private landlords must reach EPC band C on all tenancies by 1 October 2030, and "double glazing for windows" is a named fabric measure (DESNZ, January 2026). Only 32.51% of London's pre-1929 homes with an EPC reach band C (ONS, table 1c), so ask for the U-value of each window in writing.
Get quotes for a London rentalFree, no obligation
London sash window quotes: replace, refurbish or secondary glaze?
A London sash window is refurbished when the frame is sound, secondary glazed when the building is listed or the street is protected, and replaced when the frame has failed. Historic England says historic windows that add to a listed building's significance "should be retained and repaired where possible".
- Refurbish: ask whether the installer overhauls box sashes as well as replacing them.
- Secondary glaze: Historic England says it harms a listed building only if fitting it damages the frame, panelling or shutters.
- Replace: in Article 4 streets the new window must match the old, usually in timber.
Our page on window replacement in London covers the repair or replace decision in full, and sash window replacement compares the sash options.
Get London sash window quotesFree, no obligation
Before you sign
How to check a London double glazing installer
Check a London installer on public registers before the survey. London Trading Standards warns that "there are more rogue traders offering insulation, double glazing, solar panels and heat pumps" (campaign launched 18 May 2022).
- Confirm scheme registration on the FENSA installer search or the CERTASS register. In a conservation area, ask how compliance will be documented instead.
- Look the company up on Companies House: the name on the quote, the date it was set up and any past liquidation.
- Ask for an insurance-backed guarantee naming the insurer. A company-only guarantee ends if the firm stops trading. Our guide on what happens if a double glazing company goes bust covers the deposit and the guarantee.
- Ask for past work in your borough, ideally a conservation or Article 4 job, and read reviews on sites the installer does not control.
- Compare three written quotes for the same windows, using our questions to ask a double glazing salesman.
Any advert showing Martin Lewis selling windows is fake: MoneySavingExpert says he "doesn't do ads". If you sign at home, you usually have at least 14 days to cancel, but made-to-measure windows can be an exception, so check the contract before you sign (see our double glazing cooling off period guide).
Areas this page covers
London areas this page covers
This page is about homes across Greater London's 32 boroughs and the City, in places such as those below. Enter the property postcode in the form, and your enquiry goes to local installers who cover that postcode; we cannot promise cover for every street.
| Part of London | Places and postcode districts |
|---|---|
| Central | Islington and Hoxton N1, Camden Town and Marylebone NW1 |
| North | Crouch End and Hornsey N8, Enfield Town EN1, High Barnet EN5, Whetstone N20 |
| East | Dalston and Hackney Central E8, Walthamstow E17, Canning Town E16, Ilford IG1, Romford RM1, Emerson Park RM11 |
| South East | Peckham SE15, Greenwich and Blackheath SE10, Bromley BR1, Beckenham BR3, Thamesmead SE28 |
| South West | Battersea SW11, Wimbledon SW19, Croydon CR0, Kingston KT1, Sutton SM1 |
| West | Shepherd's Bush W12, Chiswick W4, Hounslow TW3, Kew and Richmond TW9, Harrow HA1, Uxbridge UB8 |
Inner London has the most sashes: 39.9% of inner London properties were built before 1919, rising to 65.0% in Kensington and Chelsea. In outer London the largest group is inter-war, at 32.5% built between 1919 and 1939 (VOA 2025), so ask for each bay as its own line.
Nearby areas
FAQ
Double glazing quotes in London, answered
Is there a government grant for double glazed windows in London?
Glazing is an eligible measure under the Warm Homes: Local Grant, which London boroughs deliver one by one. Homes under the Heathrow or London City flight paths can also check those airports' insulation schemes.
Do I need planning permission for new windows in London?
A London house usually needs no planning permission for windows of similar appearance. Flats, listed buildings, new bays and homes on Article 4 streets need permission or consent.
Which double glazing company is considered the best in the UK?
No double glazing company is officially ranked best in the UK, and we do not rank installers. Run the five checks above and compare three written quotes for the same windows.
What are people saying about Martin Lewis at Help to Buy windows?
Martin Lewis does not endorse any window scheme: MoneySavingExpert says he "doesn't do ads", so any advert linking him to Help to Buy windows is fake.
Is it worth replacing 20 year old double glazing?
Replacing 20 year old double glazing is worth it when the units have misted, the frames are draughty or the windows are hard to open, the signs the Energy Saving Trust lists. A misted pane in a sound frame often needs only a new sealed unit.
Is it worth replacing 30 year old double glazing?
Replacing 30 year old double glazing is usually worth it: the Energy Saving Trust puts the life of well-fitted double glazing at 20 to 35 years. Replace sooner when the frames or seals have failed, or when a rented home needs a better EPC before 2030.
What are the disadvantages of double glazing?
Double glazing's disadvantages are sealed units that mist as they age, airtight rooms that need trickle vents kept open, and limits in listed buildings and conservation areas (Energy Saving Trust). In many London Article 4 streets that means timber, not uPVC.
How much should I expect to pay for double glazing?
This site covers getting and comparing quotes. For prices, see what double glazing costs in London on our sister site.
How much does double glazing cost in London?
A London price depends on the number of windows, the frame material, the glass, access to upper floors and any timber a protected street requires. Three written quotes for the same specification show what your home will cost.
Get free double glazing quotes in London
Sort consent and permission first, then compare written quotes from local installers who cover your postcode. Start with double glazing quotes, or read our guide to double glazing installers.
Start my quote
Sources
Figures checked 1 October 2026.
- Census 2021 TS044 Accommodation type and TS054 Tenure, ONS via Nomis: TS044, TS054
- Valuation Office Agency, Council Tax stock of properties 2025, table CTSOP4.1
- ONS, EPC band C or above, England and Wales
- DESNZ, Improving the energy performance of privately rented homes: government response (2026)
- Planning Portal, doors and windows and change the windows of a flat
- planning.data.gov.uk, conservation area and listed building datasets (flagged incomplete)
- Kensington and Chelsea, Article 4 directions in conservation areas; Hackney, De Beauvoir conservation area; Islington, conservation areas
- Hounslow, Article 4(2) directions for Bedford Park and Gunnersbury Park
- Richmond upon Thames, Article 4 directions and conservation areas FAQ
- Havering, Gidea Park Article 4 direction; Bromley, Article 4 direction areas; Redbridge, Aldersbrook and Lake House Article 4 direction
- Heathrow, Residential Insulation Scheme FAQ and postcode checker
- London City Airport, Sound Insulation Scheme
- Historic England, modifying historic windows as part of retrofitting energy saving measures
- MoneySavingExpert, Martin Lewis scam adverts
- FENSA, fensa.org.uk; CERTASS, certass.co.uk; Which?, Trusted Traders; Companies House, company search
- London Trading Standards, doorstep crime campaign (18 May 2022)
- Energy Saving Trust, energy efficient windows and doors (updated 20 May 2026)
- Postcode districts: postcodes.io outcode lookup (ONS Postcode Directory), checked 2026-10-01
- Consumer Contracts Regulations 2013, regulation 28 and regulation 31