Guide prices in Friern Barnet
Like-for-like swap
Old dome or unit removed and disposed of, new glass rooflight fitted to the existing sound kerb
New upstand and swap
Old kerb taken off, new insulated upstand built, roof covering made good, new unit fitted
Opening or large unit
Electric or larger replacement, including making good inside
Guide ranges for supply & fit; building control notice fee extra in England and Wales. 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.
Covering N12 and neighbouring districts
Covering Friern Barnet means covering the people who live and work there, not a single postcode. We take on domestic and commercial jobs in N12, N11 and N20, and are happy to quote further out in Muswell Hill and Finchley. If your address sits between towns, tell us and we will confirm whether it falls in our normal area or needs travel set out separately on the quote.
Fit-only or supply and fit
A damaged delivery is a frequent snag on fit-only work. Before the day, unpack a replacement rooflight, photograph it, and tell the seller about any cracks or scuffs, because claims are much easier made early. We will also ask for the model or a link, so we can read the maker's instructions and check the builder's opening size and the upstand height it expects. If everything lines up, we fit it. If not, we explain what needs changing first.
What the job includes
- Building notice given to the council in England and Wales, with its fee on the quote
- Roof membrane repaired and turned up where it meets the kerb
- New unit bedded, fixed and sealed exactly as its maker shows
- Inside finishes — We check the condition of the plaster and trim around the opening from inside.
- Leaks that are not the rooflight — We look at the roof around the unit before blaming the rooflight.
What happens on the day
Where a job takes one day, the split is usually structural work first and finishing second. Early on, the fitters cut or prepare the opening, trim where needed and prepare the upstand or flashing. Then a replacement rooflight is lifted in, fixed and made weathertight so the roof is sound before anyone moves inside. Plasterboard, trim and filler for the reveal come after. Each evening the work area is swept, and at the end the glass is cleaned and the team talks you through what was done.
Do you need permission in Friern Barnet?
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
Start with your phone. Take a picture of the roof where the unit goes or already sits, then one from inside looking up. Measure what you can, even roughly. Tell us what the roof is covered with and how a fitter would reach it: ladder, garden access or scaffold. Bought it already? Send the link or spec. Add your full postcode, for example in N12, and we can price it.
Common questions in Friern Barnet
What upstand height and roof pitch does replacement rooflight fitting need?
It depends on the product. Manufacturers usually specify a minimum upstand height above the finished roof surface, and a minimum pitch on the glass so rain runs off. We follow the maker's figures for your unit rather than a rule of thumb. If your existing kerb or roof falls short, we explain the options, such as raising the upstand or choosing a unit with built-in pitch.
Can you fit the replacement rooflight I bought online?
Yes, fit-only is one of our core services. Send the product link or spec, photos of the roof and rough sizes, and we can usually price it from those. Before fitting we check the delivery for damage, which should be reported to the seller, plus the size against the builder's opening and the upstand height. The product warranty stays with the maker or seller, and our guarantee covers the fitting.
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.
Send a few photos and your N12 postcode, and we will put together a written quote for the job.

