Guide prices
Like-for-like swap
Old dome or unit removed and disposed of, new glass rooflight fitted to the existing sound kerb
New upstand and swap
Old kerb taken off, new insulated upstand built, roof covering made good, new unit fitted
Opening or large unit
Electric or larger replacement, including making good inside
Guide ranges for supply & fit; building control notice fee extra in England and Wales. 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.
Is your address covered?
Fitters travel to the job, so the address is what counts. In Trowbridge that means postcode districts BA14, BA15 and BA13, and the same teams can just as easily take on work in Westbury, about 4 miles away, or Melksham at roughly 5 miles. Survey and fitting dates are offered according to fitter availability, and travel is built into the quote rather than added later.
Buying your own, or letting us supply
Which works out better, buying your own or letting us supply? It depends on what you value. Buying your own gives you control of the product and what you pay for it. Letting us supply puts the whole job, unit and fitting, under one written quote. On a customer-supplied unit we still measure it against the opening, look at the upstand, and inspect the condition it arrived in. Warranty on the product sits with whoever sold it, while the fitting carries our own guarantee.
What the job includes
- Old rooflight or dome unscrewed, lifted out and taken away for disposal
- New unit bedded, fixed and sealed exactly as its maker shows
- Packers, an adaptor or a new insulated upstand where the old kerb falls short
- Energy rules for the new unit — We make sure the replacement meets the current energy limit, not just the old unit's performance.
- Dome to glass upgrades — We check that the opening and kerb suit a flat glass unit before quoting a dome-to-glass swap.
What happens on the day
Morning first: the team arrives, introduces itself and walks through the job with you. Dust sheets go down in the room below and along the route in. Then the opening and upstand, or the flashing on a pitched roof, are checked against the unit's measurements. A replacement rooflight goes in, is fixed to the maker's pattern and sealed into the roof covering. Inside, the reveal is finished as quoted. Before leaving, the team clears debris and talks you through what was done. Most jobs of this type take one day.
Regulations for Trowbridge properties
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 BA14. That is enough for a first price.
Common questions in Trowbridge
How long does fitting take?
Fitting a replacement rooflight 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.
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.
Do you offer trade rates for builders and roofers?
We carry out subcontract fitting for builders, roofers, extension companies and commercial contractors. Pricing is per job or per schedule of units, agreed in writing before we start. We can work to your programme, fit on your upstand or build our own, and leave the opening ready for the next trade. Send drawings or a unit schedule and we will come back with a trade quote.
Get in touch with the details of your Trowbridge property and we will explain what the job involves and what it costs.

