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RooflightInstallers.co.uk
Carshalton · SM5 · Greater London

Flat rooflight installation in Carshalton

Our guide price for flat rooflight installation starts from £995, and the real figure for your roof in Carshalton depends on a handful of things: the size and type of flat rooflight, whether the opening exists already, the roof covering, and how easy access is. We fix the price in a written quote before work begins. Nothing gets added on the day without your say-so. For a rough idea first, photos and a couple of measurements are enough to go on, and we cover all of Greater London.

Guide price from £995 · Supply & fit

Guide prices

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.

Covering SM5 and neighbouring districts

Distance is rarely the deciding factor. A roof in Wallington, 1 mile from Carshalton, gets the same survey, the same written quote and the same fitting process as one in SM5, SM1 and SM6. What changes the price is the job itself: size of unit, roof type, access and lifting. Sutton, around 2 miles out, is treated the same way.

What we check on a supplied unit

A damaged delivery is a frequent snag on fit-only work. Before the day, unpack a flat rooflight, photograph it, and tell the seller about any cracks or scuffs, because claims are much easier made early. We will also ask for the model or a link, so we can read the maker's instructions and check the builder's opening size and the upstand height it expects. If everything lines up, we fit it. If not, we explain what needs changing first.

Included in the work

  • Membrane, felt or GRP finished to the frame the way the maker shows
  • Unit bedded on the specified sealant or tape and screw-fixed
  • Reveal lined and trimmed inside, with the glass left clean
  • Ceiling and reveal depth — We measure the depth from the kerb top to the ceiling to plan the reveal.
  • Fixed or opening — We ask whether you need ventilation before you settle on a fixed unit.

What happens on the 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.

Planning and building rules in England

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.

What to send for a quick 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 SM5. That is enough for a first price.

Common questions in Carshalton

Do I need planning permission for a rooflight in Carshalton?

Often not. Many rooflights fall under permitted development, provided they do not project beyond the national limit and meet the other conditions that apply in England. Conservation areas, listed buildings and some flats are different and may need consent. Because the rules depend on the property, we confirm what is likely to apply at your address and point you to the planning authority where an application is needed.

Do you make good inside after fitting?

Yes, where the quote includes it. Internal finishing usually means lining the reveal with plasterboard, taping or skimming, and fitting trim where it meets the ceiling. Some people prefer their own plasterer or decorator to finish off, which is fine. The written quote spells out exactly where our work stops, so nobody is left guessing about who does what once the unit is in.

Can you remove and dispose of the old rooflight?

Yes. Taking out the old unit is part of any replacement job, and it leaves with the rest of the waste unless you ask to keep it. Old domes, glass and frames go through proper waste routes. If removal turns up a rotten kerb or damaged decking, we show you what we have found and agree the repair with you before going any further.

Get in touch with the details of your Carshalton property and we will explain what the job involves and what it costs.

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

Flat rooflights in Carshalton

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

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