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Derry/Londonderry · BT48 · County Londonderry

Loft conversion roof windows in Derry/Londonderry

Loft conversion roof windows in Derry/Londonderry comes down to what happens around the glass. A good unit sat on a poor upstand, or with the membrane or flashing cut short at the corners, will still let water in. We fit each loft roof window to the maker's instructions for fixings, packers and sealant, for homes and businesses across Derry/Londonderry and the rest of County Londonderry. That covers supply and fit, fit-only for a unit you already own, and swapping out a tired one. Every job starts with a written quote, so the price and scope are clear before anyone climbs a ladder.

Guide price from £1,795 · Supply & fit

Guide prices in Derry/Londonderry

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.

Coverage in and around Derry/Londonderry

Fitters travel to the job, so the address is what counts. In Derry/Londonderry that means postcode districts BT48, BT47 and BT49, and the same teams can just as easily take on work in Coleraine, about 27 miles away, or Omagh at roughly 27 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

Your unit or ours, the fitting standard is the same. For supply and fit we choose a loft roof window to suit the roof and price it with the installation. For fit-only we work with what you have, after confirming it arrived undamaged, that it matches the builder's opening, and that the upstand will sit at the height the maker asks for. Report any transit damage to the seller, as the product cover is theirs and the maker's. Our written guarantee applies to the fitting itself.

What we do on the day

  • Matching or combination flashing kits for windows side by side
  • Window positions set out on the slope to line up inside and out
  • Tiles or slates cut and refitted, with the roof left weathertight
  • Fitting stage and weather — We plan when the windows go in around the rest of the conversion.
  • Balcony-style windows — We check the rafters and the roof pitch before recommending balcony-style windows.

Fitting your loft roof window, step by step

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.

Regulations for Derry/Londonderry properties

Northern Ireland's building regulations set a minimum of WER Band C or 1.6 W/m²K for rooflights and roof windows in existing homes, assessed under Technical Booklet F1. New openings involve trimming the roof structure, so expect a building control application. Many house rooflights don't need planning permission, but conservation areas and listed buildings are excluded, and side windows near a boundary have obscure-glazing rules. We confirm what applies.

Help us quote accurately

Each detail you send takes a question off our list. Photos inside and out show the opening and the ceiling. Rough measurements tell us the unit size. The roof covering tells us how it will be sealed in. Access notes tell us whether a tower or scaffold is needed. A product link, if you have one, lets us check it against the opening. Your postcode, BT48 or nearby, confirms travel.

Common questions in Derry/Londonderry

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 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.

Do you cover Derry/Londonderry?

Yes. Fitters travel to addresses in Derry/Londonderry and the surrounding districts, including BT48. 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.

For a free, no-obligation quote in Derry/Londonderry, use the form or call us with the details of your roof.

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

Loft roof windows in Derry/Londonderry

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

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