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RooflightInstallers.co.uk
Friern Barnet · N12 · Greater London

Sliding rooflight installation in Friern Barnet

Rooflight work is weather work. Membranes, primers and sealants all want a dry surface, so a fitting day in Friern Barnet is planned around the forecast rather than pinned to a date regardless of rain. The opening is kept covered whenever it is exposed, and a roof is not left open overnight without a proper temporary seal. That approach applies to every sliding rooflight we install, from a new opening to a straight swap or a fit-only job. We cover Friern Barnet, the N12 district and the rest of Greater London.

Guide price from £7,795 · Supply & fit

Guide prices in Friern Barnet

Compact sliding

£7,795 – £10,795including VAT at 20%

Motorised sliding unit for a stair or hatch opening

Standard sliding

£10,795 – £15,595including VAT at 20%

Larger opening onto a roof terrace

Large sliding

£15,595 – £22,795including VAT at 20%

Big spans, lifting gear and longer installs

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 Friern Barnet we cover

Our fitters come to you. For Friern Barnet that covers N12, N11 and N20, plus nearby Muswell Hill and Finchley. We do not keep a yard or showroom in the area, and you do not need to visit one. The survey happens at your property or, for fit-only work, from the photos you send. Dates follow fitter availability, which we confirm when you accept the quote.

Fit-only or supply and fit

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 sliding rooflight 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

  • Full open and close cycle checked before handover
  • Upstand checked for strength, square and level along its full length
  • Cable routed to the motor, ready for the electrician's final connection, quoted as a separate line
  • What the glass slides over — We check the area the glass will cover when open before deciding where the unit goes.
  • Power and safety stops — We confirm the power supply and the safety features before fitting day.

Fitting your sliding rooflight, step by step

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 sliding rooflight 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.

Planning, building control and 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

How long does fitting take?

Fitting a sliding rooflight into an existing, correctly sized opening is often a day's work. New openings take longer, because joists or rafters need trimming, an upstand or flashing has to be built or fitted, and the inside needs finishing. Large units that need lifting gear, and days lost to rain, can stretch things further. Your written quote gives a realistic estimate for your roof.

What upstand height and roof pitch does sliding 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.

What if my roof opening is the wrong size for the sliding rooflight?

We find out before the fitting day, not on it. If the opening is slightly out, it can usually be adjusted by trimming or by packing out the upstand. If it is a long way off, the choice is between altering the opening and changing the unit. Bear in mind that rooflights are often sold by builder's opening size rather than external size, so check which one your measurement refers to.

Get in touch with the details of your Friern Barnet property and we will explain what the job involves and what it costs.

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

Sliding rooflights in Friern Barnet

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

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