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Dorchester · DT1 · Dorset

Sun tunnel installation in Dorchester

Cut the opening. Trim the joists or rafters. Build the upstand or fit the flashing kit. Fix the unit, seal it, finish the inside. On a new opening, that is the whole job in plain terms, and each step has to be right for the next one to work. We carry out this work in Dorchester and across Dorset, either installing a unit you have bought or sourcing one for you. You get a written quote with the scope set out, and a written workmanship guarantee on the fitting with its terms on that quote.

Guide price from £595 · Supply & fit

Guide prices in Dorchester

Short rigid tube

£595 – £845including VAT at 20%

Around 250 mm tube, short straight run through a loft

Wider or longer run

£845 – £1,145including VAT at 20%

Around 350 mm tube or longer runs with bends

Flat roof or complex

£1,145 – £1,745including VAT at 20%

Flat roof kits, long runs or two tubes

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.

Areas around Dorchester we cover

Looking at a property near Dorchester but not quite in it? We work across DT1, DT2 and DT3 and outwards to Weymouth, Yeovil and Poole. Give us the full postcode when you get in touch, because access, parking and the route for a large unit all depend on the exact street. Those details shape the quote for any job around Dorchester.

What we check on a supplied unit

Supply and fit tends to suit people who would rather not pick a unit from a catalogue. We look at the roof, the opening and how you use the room, then put a sun tunnel on the quote that fits all three. Fit-only suits people who already know what they want, or have one on site. We are happy with either. The difference is who stands behind what: on fit-only, the maker or retailer covers the product, and our workmanship guarantee covers the installation.

What the job includes

  • Rigid or flexible tube run and joined, with as few bends as possible
  • Dome fixed and sealed on top of the flashing
  • Tube insulated where it passes through a cold loft
  • Length and bends in the tube — We plan the shortest, straightest route we can between the roof and the ceiling.
  • Rigid or flexible tube — We check whether a rigid tube will fit the route before falling back on a flexible one.

From arrival to clean-up

Fitting days start with a look at the sky. If rain is due, the order of work changes so the roof is never left open to it. A typical day for a sun tunnel runs like this: set up access, protect the room, open up the roof or prepare the existing kerb or frame, check sizes, fix, seal, then finish inside. On jobs that take more than a day, the opening is weather-sealed overnight. The last hour goes on tidying, waste removal and a walk-round with you.

Do you need permission in 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.

Details that speed up your quote

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 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.

Will my new sun tunnel leak?

A correctly fitted unit should not. Leaks usually trace back to the detail around the frame: an upstand that is too low, a membrane or flashing that is not dressed properly, sealant applied to a damp surface, or water ponding against the kerb. We fit to the maker's instructions and check each of those points. The fitting carries a written workmanship guarantee, with its terms set out on your quote.

What is included in the price?

The written quote lists it line by line. Typically that covers fitting labour, fixings, sealants, membrane or flashing materials, any upstand work, internal finishing if agreed, and taking away the waste. For supply and fit, the unit itself is included too. Scaffold, lifting gear and any third-party fees, where needed, are shown separately so you can see what each part of the job costs.

Got a unit waiting to go in, or need one sourced? Either way, start with your Dorchester address and a couple of photos.

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

Sun tunnels 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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