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RooflightInstallers.co.uk
Dorchester · DT1 · Dorset

Walk-on rooflight installation in Dorchester

Rooflight work is weather work. Membranes, primers and sealants all want a dry surface, so a fitting day in Dorchester is planned around the forecast rather than pinned to a date regardless of rain. The opening is kept covered whenever it is exposed, and a roof is not left open overnight without a proper temporary seal. That approach applies to every walk-on rooflight we install, from a new opening to a straight swap or a fit-only job. We cover Dorchester, the DT1 district and the rest of Dorset.

Guide price from £3,345 · Supply & fit

Guide prices in Dorchester

Up to 1 m²

£3,345 – £4,545including VAT at 20%

Laminated walk-on unit with anti-slip finish, fitted level with the terrace

Up to 2 m²

£4,545 – £7,195including VAT at 20%

Larger walk-on glazing

Large or bespoke

£7,195 – £11,995including VAT at 20%

Big panes, structural calculations, 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

Fitters travel to the job, so the address is what counts. In Dorchester that means postcode districts DT1, DT2 and DT3, and the same teams can just as easily take on work in Weymouth, about 7 miles away, or Yeovil at roughly 18 miles. Survey and fitting dates are offered according to fitter availability, and travel is built into the quote rather than added later.

Fit-only or supply and fit

If you have bought a walk-on 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.

On the day, we cover

  • Engineer's calculations and the unit's loading data checked together
  • Support frame or upstand prepared to the approved structural design
  • Lifting plan for the unit, including people or gear for the day
  • Structural calculations — We need structural calculations for the glass and its support before a walk-on job goes ahead.
  • Units tested to old standards — We check which standard the walk-on unit has been tested to.

From arrival to clean-up

Arrive and agree the plan. Sheet the floor and furniture. Set up the ladder, tower or scaffold. Check the opening, the upstand or flashing, and the unit against the paperwork. Fix and pack a walk-on rooflight level. Seal it into the roof. Line the reveal or fit the ceiling trim. Clean the glass, clear the waste, and talk you through it. That is the shape of most fitting days, and for this type of job it usually takes one to two days.

Planning, building control and Dorchester

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.

Getting a price from photos

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, DT1 or a neighbouring district.

Common questions in Dorchester

Can you replace an old dome without redoing the whole roof?

Usually, yes. If the existing kerb is sound, level and tall enough, a new unit can often sit on it with a fresh seal to the roof covering. If the kerb is rotten or too low, we rebuild it and patch the covering around it rather than stripping the whole roof. This is checked at the survey and included in the written quote, so you know the full scope first.

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.

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.

Questions before you commit? Send them over with your Dorchester postcode and we will answer them plainly, with a quote alongside.

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

Walk-on rooflights in Dorchester

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

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