- Certified Installation Professionals
- All London boroughs covered
- Free, no-obligation quotes
- Certified Installation Pros
- All Across London
Arbor Skylights specialises in flat roof window replacement across London, upgrading old domes and leaking rooflights in areas including Kilburn, Queen’s Park and West Hampstead. We remove the old unit, check and rebuild the upstand where needed, and fit a modern, well-insulated flat roof window that stays watertight.
We are Velux-certified specialists
Not general builders, pros only
We provide turnkey solutions
Many London extensions built in the 1980s, 90s and 2000s still have their original rooflights: plastic domes that have gone cloudy, early double glazing, and upstands that have started to let water in. They lose heat, drip condensation and spoil the look of the room.
Arbor Skylights replaces old and failing flat roof windows across London, including Kentish Town, Kensal Rise and Willesden. Whether you want a like-for-like swap or an upgrade from a dome to a sleek flat-glass rooflight, we’ll recommend the right option for your roof and budget.
Every replacement is completed with careful attention to the upstand, insulation and seal, so the new window performs as part of the roof for years to come.
Most rooflight leaks start at the upstand and seal, so we check both on every job.
If a new dome on a sound upstand will do, we'll tell you before recommending a full upgrade.
Modern glazing and insulated upstands cut heat loss and condensation.
We replace rooflights in felt, EPDM, GRP and single-ply roofs.
Most replacements are completed in a day, with the room protected throughout.
A properly sealed replacement is designed to stay watertight for decades.
We offer a full range of flat roof window replacement services across London, matched to the condition of your existing rooflight and roof.
The most popular upgrade: a minimal, modern look with much better insulation.
A new dome on the existing upstand, a quick and affordable fix where the upstand is sound.
Failed rooflights replaced and resealed so the leak doesn't come back.
Rotten or poorly insulated upstands rebuilt and insulated before the new window goes in.
Add ventilation with a manual or electric opening rooflight.
Where joists allow, a bigger opening brings in significantly more light.
Arbor Skylights provides professional flat roof window replacement across London, upgrading old and leaking rooflights for homes in areas including West Hampstead, Kentish Town and Kensal Rise. Every replacement is fitted to the same standard for weatherproofing, insulation and finish.
Over time, flat roof windows lose performance as domes yellow, seals fail and upstands deteriorate. Replacing them stops leaks and condensation, keeps the room warmer and refreshes the look of an extension.
Modern flat roof windows offer much better thermal performance, clearer glass and options such as solar-control glazing, opening vents and blinds. Whether you’re replacing one rooflight or several, we’ll recommend the right specification.
We survey the existing rooflight, upstand and roof covering before we quote, and explain clearly whether the upstand can be reused. From first contact to handover, we provide a professional replacement service across North West London, including Kilburn, Queen’s Park, Willesden and Highbury.
1. Send photos
Pictures of the rooflight from inside and, if safe, from above help us plan.
2. Survey and fixed quote
We measure the upstand and confirm the replacement option.
3. Replacement
Most replacements take 1 day, or 2 if the upstand needs rebuilding.
4. Finishing
We make good the reveal, test any opening function and clean up.
Improved energy efficiency. Modern glazing and insulated upstands keep heat in.
No more leaks. A properly sealed upstand protects against London's wettest weather.
Less condensation. Warmer glass and frames mean far fewer drips in cold weather.
Clearer, brighter light. Replacing cloudy or yellowed domes restores full daylight.
A modern look. Flat-glass rooflights give extensions a clean, contemporary finish.
Ventilation options. Upgrade to an opening rooflight for fresh air.
We replace flat roof windows throughout London, with regular work in Kilburn, Queen’s Park, West Hampstead, Kentish Town, Kensal Rise, Willesden and Highbury.
We also cover Islington, Camden and Finchley in the North; Hackney and Walthamstow in the East; Ealing, Chiswick and Kensington in the West; Clapham, Wandsworth and Richmond in the South West; and Dulwich, Greenwich and Blackheath in the South East. Not sure we cover your street? Send us your postcode.
Yes, in most cases. The new flat glass rooflight is fitted on the existing upstand if it is sound and the right size, or on a new insulated upstand if not.
Most flat roof window leaks come from a failed seal between the upstand and the roof covering, a cracked dome or a failed glazing unit. We find the cause first, then recommend a repair or replacement.
Sometimes. If the upstand and frame are sound and only the seal has failed, a repair may be enough. Cracked domes, failed glazing and rotten upstands are usually better value to replace.
Often, yes. We measure the upstand and check its condition at the survey. If it’s rotten, too low or poorly insulated, we rebuild it.
Most replacements take 1 day. If the upstand needs rebuilding or the opening is being enlarged, allow 2 days.
The cost depends on the size, the glazing and whether the upstand can be reused. Like-for-like domes are the most affordable; dome-to-flat-glass upgrades cost more. We give a fixed price after seeing photos or surveying the roof.
Usually not, if the replacement is a similar size and does not project more than 150mm above the roof. Listed buildings and some conservation areas may need consent.
Old single-glazed domes and poorly insulated upstands are cold surfaces, so warm, moist air condenses on them. A modern double or triple-glazed rooflight on an insulated upstand greatly reduces this.
Yes. A fixed dome or rooflight can be replaced with a manual or electric opening unit for ventilation.
Yes. Replacing several rooflights in one visit gives a consistent look and is usually more cost-effective.
