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RooflightInstallers.co.uk
Dorchester · DT1 · Dorset

Flat rooflight installation in Dorchester

Plenty of rooflight trouble starts with a tape measure. Units are often sold by the builder's opening, meaning the hole in the roof, rather than the overall external size, and confusing the two leaves you with a frame that does not suit the opening. Before we fit any flat rooflight in Dorchester, we measure the opening, the upstand or kerb where there is one, and the finished roof level, then compare them with the maker's drawing. If something is out, you hear about it before the fitting day rather than on it. That single check keeps most jobs like this on track.

Guide price from £995 · Supply & fit

Dorchester 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.

Coverage in and around Dorchester

Dorchester and the districts around it, DT1, DT2 and DT3, all sit inside our working area. So does the ground between Dorchester and Weymouth (7 miles), and on towards Yeovil (18 miles). When a fitting team is booked, their travel is already in the quoted price, so it does not turn up as a surprise line on the final bill.

Already bought your unit?

Your unit or ours, the fitting standard is the same. For supply and fit we choose a flat rooflight 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.

Included in the work

  • Unit bedded on the specified sealant or tape and screw-fixed
  • Reveal lined and trimmed inside, with the glass left clean
  • Membrane, felt or GRP finished to the frame the way the maker shows
  • Pitch of the glass — We make sure the glass will sit at the pitch its maker asks for.
  • Ceiling and reveal depth — We measure the depth from the kerb top to the ceiling to plan the reveal.

Fitting your flat rooflight, step by step

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 flat 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.

Planning, building control and Dorchester

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.

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.

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.

For a free, no-obligation quote in Dorchester, use the form or call us with the details of your roof.

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

Flat 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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