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RooflightInstallers.co.uk
Isleworth · TW7 · Greater London

Flat rooflight installation in Isleworth

Already bought a flat rooflight, or still deciding which one to get? Both are fine. For flat rooflight installation in Isleworth 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 TW7 and the surrounding districts are covered on the same terms.

Guide price from £995 · Supply & fit

What the job costs in Isleworth

Small fixed

£995 – £1,495including VAT at 20%

Double-glazed fixed unit up to 1000 × 1000 mm, fitted to a ready upstand

Medium fixed

£1,495 – £2,295including VAT at 20%

1000 × 1500 to 1000 × 2000 mm, double or triple glazed

Large fixed

£2,295 – £4,095including VAT at 20%

Bigger units, solar-control glass, two-person lift or lifting gear

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.

Where our fitters travel

If you also own a property or a business unit in Hounslow, Heston or Richmond, that is no problem. We can survey and quote both, and where it suits, line the fitting days up together. Every address is reached by fitters travelling to it from their current jobs, and TW7, TW3 and TW5 sit comfortably within that pattern.

Fit-only or supply and fit

If you have bought a flat rooflight yourself, we check four things before fitting. First, the delivery: open it, look for chips, cracks and bent frames, and report any damage to the seller straight away. Second, the size, measured against the builder's opening rather than the external frame. Third, the upstand height above the finished roof. Fourth, the maker's instructions, which set the fixings and sealing. Product warranty claims go to the seller and maker; our guarantee is for how it was fitted.

What the job includes

  • Upstand checked or built to the maker's internal and external sizes
  • Reveal lined and trimmed inside, with the glass left clean
  • Unit bedded on the specified sealant or tape and screw-fixed
  • Solar gain on south-facing roofs — We ask which way the roof faces and how the room is used before suggesting glass.
  • Fixed or opening — We ask whether you need ventilation before you settle on a fixed unit.

A typical installation day

Protection comes before tools. Floors, furniture and stairs get covered, and the ceiling below the opening is sheeted to catch dust. Up top, the fitters confirm the opening is square and the upstand or flashing suits what the maker specifies. Fixing follows, then weather-sealing into the membrane, felt or tiles. Only once the roof is tight do they turn to the internal reveal. Time on site for a flat rooflight: one day, weather permitting.

Regulations for Isleworth properties

In England, a new rooflight opening generally needs building regulations approval because the roof structure is altered and the glazing must meet energy rules: 2.2 W/m²K for a rooflight in an existing home, or 1.4 W/m²K (or WER Band B) for a roof window. Planning is often not needed on a house: permitted development covers rooflights that stand no more than 0.15 m proud of the roof slope and sit below the highest part of the roof. Flats, listed buildings and areas with an Article 4 direction are different, so we check your address first.

Details that speed up your quote

Keep it simple. Two or three photos, outside and inside. Approximate sizes. What the roof is made of. Anything awkward about getting up there, such as a conservatory below, a narrow side path or no parking. If you bought the rooflight online, the link or model name. Then your postcode in or around TW7. That is enough for a first price.

Common questions in Isleworth

Do you need scaffolding to fit a rooflight?

Not always. Single-storey roofs can often be reached safely with ladders, a tower or edge protection. Higher roofs, steep pitches and large units usually need scaffold or a mobile platform, and heavy glass may need a crane. We assess access from your photos or at the survey, and any scaffold or lifting cost is shown as its own line on the written quote.

Can you fit the flat rooflight I bought online?

Yes, fit-only is one of our core services. Send the product link or spec, photos of the roof and rough sizes, and we can usually price it from those. Before fitting we check the delivery for damage, which should be reported to the seller, plus the size against the builder's opening and the upstand height. The product warranty stays with the maker or seller, and our guarantee covers the fitting.

What if my roof opening is the wrong size for the flat rooflight?

We find out before the fitting day, not on it. If the opening is slightly out, it can usually be adjusted by trimming or by packing out the upstand. If it is a long way off, the choice is between altering the opening and changing the unit. Bear in mind that rooflights are often sold by builder's opening size rather than external size, so check which one your measurement refers to.

Got a unit waiting to go in, or need one sourced? Either way, start with your Isleworth address and a couple of photos.

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

Flat rooflights in Isleworth

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

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