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RooflightInstallers.co.uk
Chelsea · SW3 · Greater London

Loft conversion roof windows in Chelsea

Already bought a loft roof window, or still deciding which one to get? Both are fine. For loft conversion roof windows in Chelsea we either source a suitable unit and install it, or fit the one waiting in your garage. Fit-only jobs are usually priced from your photos and measurements, while supply-and-fit and replacement jobs get a free survey first. Whichever route you take, the opening, the upstand or flashing, and the delivery are checked before anything is fixed down. Properties in SW3 and the surrounding districts are covered on the same terms.

Guide price from £1,795 · Supply & fit

Chelsea guide prices

Pair of windows

£1,795 – £2,745including VAT at 20%

Two roof windows into a loft room, flashings and linings

Three or four windows

£2,745 – £4,545including VAT at 20%

Bigger loft rooms or stairwells

Balcony or combination

£4,545 – £7,195including VAT at 20%

Balcony-style or stacked window combinations

Guide ranges for supply & fit. Your price is fixed in a written quote after we have seen photos or surveyed. Scaffold, access towers or a crane are priced separately if the job needs them, and building control fees, where a job needs them, are shown as their own line.

Fitting across Chelsea and nearby

Jobs across SW3, SW10 and SW7 are part of our normal cover for Chelsea. We are not an office on the high street. Our fitting teams come out to the property from wherever they are working that week. Neighbouring places such as Battersea and Kensington are covered on the same terms, so a house on the edge of town is no harder to book than one in the centre.

Fit-only or supply and fit

There are two ways to do this. Supply and fit means we source a loft roof window that suits your roof and install it, so one company answers for both the product choice and the fitting. Fit-only means you buy the unit and we install it. With fit-only, the product warranty stays with the maker or seller, and our written guarantee covers the fitting work. Both routes get the same checks on the opening, the upstand and the maker's instructions before anything is fixed.

On the day, we cover

  • Matching or combination flashing kits for windows side by side
  • Linings fitted, ready for the plasterboarder or decorator
  • Rafters trimmed and doubled where the openings need them
  • Approved loft drawings — We work to the window positions on your approved loft drawings or agree changes with your builder first.
  • Energy performance in a loft — We check every window meets the energy limit for roof windows in existing homes.

A typical installation day

Where a job takes one to two days, the split is usually structural work first and finishing second. Early on, the fitters cut or prepare the opening, trim where needed and prepare the upstand or flashing. Then a loft roof window is lifted in, fixed and made weathertight so the roof is sound before anyone moves inside. Plasterboard, trim and filler for the reveal come after. Each evening the work area is swept, and at the end the glass is cleaned and the team talks you through what was done.

Do you need permission in Chelsea?

England's rules in short: permitted development usually covers a rooflight on a house roof provided it doesn't stick out more than 0.15 m or rise above the ridge, though a listed building always needs consent and some streets have Article 4 directions. Building regulations apply to new openings, and replacements go through building control; as we are not registered with a competent person scheme, we use a building notice and show the fee on the quote. The energy limit for rooflights in existing homes is 2.2 W/m²K, and the 2026 Approved Document L, in force from 24 March 2027, keeps that figure.

Help us quote accurately

What we cannot see, we have to guess, and guesses make quotes wider. So the more you send, the tighter the price. Useful: shots from the roof or garden, shots from the room underneath, a rough width and length, the roof finish, any access problems, and the product page if you have already ordered. Add the property postcode around SW3 and we will come back with a quote or a survey date.

Common questions in Chelsea

How does payment work?

Payment terms are set out on your written quote before you accept it. Depending on the job, that may mean a deposit, stage payments for larger work, or payment on completion. The contract is with S&K Property Investments and Improvement Ltd, part of the S&K Group. Nothing is added without your agreement: if something unexpected comes up, we discuss it and agree any change before carrying on.

Does a rooflight need building regulations approval?

A new opening usually needs building regulations approval. A replacement is a controlled fitting: it must be self-certified by an installer registered with a competent person scheme or notified to building control. We are not registered with a scheme, so replacements we fit are notified to building control with a building notice, and the council's fee is shown on your quote.

How long does fitting take?

Fitting a loft roof window into an existing, correctly sized opening is often a day's work. New openings take longer, because joists or rafters need trimming, an upstand or flashing has to be built or fitted, and the inside needs finishing. Large units that need lifting gear, and days lost to rain, can stretch things further. Your written quote gives a realistic estimate for your roof.

Planning a loft roof window in Chelsea? Tell us about the roof and we will come back with a clear price in writing.

Rear extension at dusk with lit rooflights and a roof lantern
Ready when you are

Loft roof windows in Chelsea

Send photos and rough sizes, or ask for a survey for install work. One fixed written price before anything starts.

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