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Caernarfon · LL55 · Gwynedd & Anglesey

Rooflight upstands & kerbs in Caernarfon

Replacing an old dome or a failed rooflight often means the kerb underneath has to change too: it may be rotten, too low for the new unit or the wrong size. We strip back what is needed, build a new upstand in Caernarfon to the new unit's dimensions, insulate it and dress the roof covering up to it. Where only part of the kerb has failed, we say so and price the smaller repair. The scope is set out in a written quote before work starts.

Guide price from £245 · Labour and materials, rooflight not included

Guide prices in Caernarfon

Timber upstand

£245 – £445including VAT at 20%

Treated timber kerb built square and level to the maker's size

Insulated upstand

£445 – £845including VAT at 20%

Kerb with insulation and the roof membrane turned up and dressed

Large or with trimming

£845 – £1,445including VAT at 20%

Bigger kerbs or where joists need trimming first

Guide ranges for labour and materials, rooflight not included. 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

Looking at a property near Caernarfon but not quite in it? We work across LL55, LL61 and LL56 and outwards to Bangor, Holyhead and Llandudno. 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 Caernarfon.

Included in the work

  • Treated timber frame fixed down to the deck and joists
  • Kerb sized from the maker's drawing, internal and external dimensions both checked
  • Diagonals measured so the kerb is square before anything sits on it
  • Energy limit for site-built kerbs — We insulate upstands to meet the limit for site-built upstands, which is 0.35 W/m²K in England and Wales.
  • Height above the finished roof — We set the upstand so it stands at least 150 mm above the finished roof, measured from the top of any ballast, paving or walkway.

From arrival to clean-up

On the day, the fitters check the opening and the roof deck around it, then cut and fix treated timber to the maker's kerb size, square and level, with any fall the rooflight needs built in. Insulation goes on the faces that need it, and the roof membrane is turned up and dressed so the kerb is weathertight before anyone leaves. Most upstand jobs take half a day to a day.

Planning and building rules in Wales

Welsh rules differ from England's in one important way: rooflights lose permitted development rights in conservation areas, National Parks, AONBs and World Heritage Sites. Elsewhere on a house, a rooflight that projects no more than 150 mm and stays below the highest part of the roof is usually fine. Building regulations still apply to new openings, replacements we fit go through a building notice because we are not scheme-registered, and the energy limit for rooflights is 2.2 W/m²K. A new Welsh Approved Document L takes effect on 4 March 2027.

Getting a price from photos

What we cannot see, we have to guess, and guesses make quotes wider. So the more you send, the tighter the price. Useful: shots from the roof or garden, shots from the room underneath, a rough width and length, the roof finish, any access problems, and the product page if you have already ordered. Add the property postcode around LL55 and we will come back with a quote or a survey date.

Common questions in Caernarfon

Do you cover Caernarfon?

Yes. Fitters travel to addresses in Caernarfon and the surrounding districts, including LL55. We do not run an office there; the survey and the fitting happen at your property. A few island and remote postcodes are covered by arrangement; if yours is one, we confirm travel and dates before quoting.

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.

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.

Send a few photos and your LL55 postcode, and we will put together a written quote for the job.

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

Upstands & kerbs in Caernarfon

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

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