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RooflightInstallers.co.uk
Hounslow · TW3 · Greater London

Loft conversion roof windows in Hounslow

Our guide price for loft conversion roof windows starts from £1,795, and the real figure for your roof in Hounslow depends on a handful of things: the size and type of loft roof window, 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 £1,795 · Supply & fit

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.

Coverage in and around Hounslow

If you also own a property or a business unit in Isleworth, Heston or Twickenham, 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 TW3, TW4 and TW5 sit comfortably within that pattern.

Fit-only or supply and fit

Your unit or ours, the fitting standard is the same. For supply and fit we choose a loft roof window to suit the roof and price it with the installation. For fit-only we work with what you have, after confirming it arrived undamaged, that it matches the builder's opening, and that the upstand will sit at the height the maker asks for. Report any transit damage to the seller, as the product cover is theirs and the maker's. Our written guarantee applies to the fitting itself.

What the job includes

  • Linings fitted, ready for the plasterboarder or decorator
  • Window positions set out on the slope to line up inside and out
  • Underlay dressed and taped around every frame
  • Combination flashings — We order combination flashings where windows sit close together.
  • Energy performance in a loft — We check every window meets the energy limit for roof windows in existing homes.

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 loft roof window: one to two days, 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.

Before you get in touch

A fast quote needs five things: a photo of the roof from outside, one from the room below, rough sizes of the opening or the space, the roof covering (felt, single-ply, fibreglass, tiles, slate or metal), and a note on access. If you have already bought the unit, add the product link or spec sheet. And give us the postcode, TW3 or a neighbouring district.

Common questions in Hounslow

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.

Can you fit the loft roof window 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 opening, the flashing kit and the roof pitch. The product warranty stays with the maker or seller, and our guarantee covers the fitting.

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 Hounslow 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

Loft roof windows in Hounslow

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

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