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RooflightInstallers.co.uk
St Austell · PL25 · Cornwall

Loft conversion roof windows in St Austell

Glass is heavy, and bigger units get heavy fast. Fitting a loft roof window in St Austell means planning how it travels from the delivery vehicle to the roof without chipping an edge or straining a back. Smaller units go up by hand with two fitters. Larger ones may need a hoist, a scaffold loading bay or a crane, and we tell you at quote stage if that applies. Once it is up, the fitting follows the maker's sequence: seat, fix, seal, finish. We take on work like this across Cornwall.

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.

Fitting across St Austell and nearby

St Austell and the districts around it, PL25, PL26 and PL24, all sit inside our working area. So does the ground between St Austell and Bodmin (9 miles), and on towards Truro (13 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.

What we check on a supplied unit

There are two ways to do this. Supply and fit means we source a loft roof window that suits your roof and install it, so one company answers for both the product choice and the fitting. Fit-only means you buy the unit and we install it. With fit-only, the product warranty stays with the maker or seller, and our written guarantee covers the fitting work. Both routes get the same checks on the opening, the upstand and the maker's instructions before anything is fixed.

Included in the work

  • Tiles or slates cut and refitted, with the roof left weathertight
  • Insulation collars fitted so the room's insulation meets each frame
  • Matching or combination flashing kits for windows side by side
  • Combination flashings — We order combination flashings where windows sit close together.
  • Fitting stage and weather — We plan when the windows go in around the rest of the conversion.

A typical installation 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

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.

Help us quote accurately

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 PL25. That is enough for a first price.

Common questions in St Austell

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.

Does a rooflight need building regulations approval?

A new opening usually needs building regulations approval. A replacement is a controlled fitting: it must be self-certified by an installer registered with a competent person scheme or notified to building control. We are not registered with a scheme, so replacements we fit are notified to building control with a building notice, and the council's fee is shown 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 St Austell address and a couple of photos.

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

Loft roof windows in St Austell

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

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