Guide prices in Friern Barnet
Pair of windows
Two roof windows into a loft room, flashings and linings
Three or four windows
Bigger loft rooms or stairwells
Balcony or combination
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 Friern Barnet and nearby
Fitters travel to the job, so the address is what counts. In Friern Barnet that means postcode districts N12, N11 and N20, and the same teams can just as easily take on work in Muswell Hill, about 2 miles away, or Finchley at roughly 2 miles. Survey and fitting dates are offered according to fitter availability, and travel is built into the quote rather than added later.
Buying your own, or letting us supply
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.
What the job includes
- Underlay dressed and taped around every frame
- Matching or combination flashing kits for windows side by side
- Tiles or slates cut and refitted, with the roof left weathertight
- Balcony-style windows — We check the rafters and the roof pitch before recommending balcony-style windows.
- Approved loft drawings — We work to the window positions on your approved loft drawings or agree changes with your builder first.
How a fitting day runs
On the day, you need to be in at the start and at the end. In between, the fitters get on with it. They will want the room below cleared where possible, a parking spot if you have one, and somewhere to set the unit down safely. After checking the opening and the upstand or flashing, they fix a loft roof window, seal it and finish the inside. Packaging and any old unit leave with them unless the quote says otherwise.
Planning, building control and Friern Barnet
Replacing a rooflight in an English home is a controlled fitting: it has to be self-certified by a scheme-registered installer or notified to building control. We are not registered with a competent person scheme, so replacements we fit are notified with a building notice, and the new unit has to meet current energy limits. Adding a new one usually means a building regulations application, because joists or rafters are trimmed. On the planning side, most house rooflights are permitted development if they project 0.15 m or less; on a side slope the glass must be obscured and fixed unless the opening part is over 1.7 m above the floor.
What to send for a quick 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, N12 or a neighbouring district.
Common questions in Friern Barnet
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.
Can you fit a rooflight in winter or when it is raining?
Yes, within limits. Cold is less of a problem than wet, because membranes, primers and sealants need a dry surface to bond. We plan fitting days around the forecast and may move a date if heavy rain is due. If the roof has to be opened up, it is not left overnight without a temporary weather seal, so the room below stays dry while the work is finished.
Will my new loft roof window 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.
Tell us your postcode, N12 or close by, and what you want fitted. We will reply with the next steps and a quote.

