How much does it cost to get a roof window installed?

A roof window is bought by size, and a wider or taller sash costs more than a small one because there is more frame, more glass and more flashing around it. The type matters as well. A centre-pivot sash rotates around a central axis, which suits a room with furniture below the glass. A top-hung sash is hinged at the head and swings outward, leaving headroom beneath. Each is made in its own range, and an electric opening model sits above a manual one because of the motor and controls.

Glazing moves the figure too. Start with double glazing; a triple pane or a solar-control coating adds to the figure. The extra spend buys a lower U-value, which cuts the heat escaping. VELUX size codes are explained in choosing the VELUX window size.

The covering around a roof window is cut and rebuilt, so what lies on the roof shapes the work. Each covering has its own flashing kit, from thin Welsh slate to deep-profile concrete tile. A roof that has been altered several times, or that carries old felt and wide laths, may need more work before the new frame can sit square in it.

A new opening also alters the roof structure. A rafter or two may be trimmed and carried on either side. Replacing an existing roof window in the same opening is simpler than cutting a new one, and that difference shows in the quote, and both jobs are described in roof window installation in Leeds.

A bungalow roof can be reached from a ladder, while a three-storey Victorian villa may need scaffold, and the extra equipment goes into the figure. A back slope above a narrow yard can be harder to work on than a front slope above a street, and a roof with no safe place to stand adds time. Those are matters of the building, so we look at them in the survey.

The inside of the opening is made good as well. Where a loft void lies above the ceiling, a light well is built down through it, insulated and plastered, and a tall well takes more time than a short reveal. The lining is covered in light wells and reveals for roof windows. Two windows of the same size can come out at different totals for this reason alone.

Some choices sit on top of the basic window and move the total. A blind adds a little, and a blackout or pleated blind is made to fit the sash of the window it goes on. An electric opening window needs a power supply to the opening, which can mean a cable run through the loft, and a rain sensor is built into many models. Two windows side by side, or one above another, are fitted with a combination flashing made for the pair.

Taking out the old window and clearing away the slates, felt and plaster is part of a replacement. A window being replaced like for like, in the same opening, usually costs less than a larger one, because the rafters stay where they are. The same factors for that make are worked through in VELUX window installation cost.

A sun tunnel is a different product with a different price, and for a small landing or bathroom it can be the lighter job. Our comparison of sun tunnels with roof windows sets out when each suits.

Because the price depends on the roof, the room and the access, it is worked out after the free survey. The written quote then gives one set figure for the window and its size in your room. Where a new opening is cut, we notify Building Control. Nothing is added on the day for things we could see at the survey.

We look up planning and conservation status first, and the finished window carries a 10-year workmanship guarantee from us (see the guarantee page). For a landing that never gets enough light, a roof window over the stairs shows where we begin. To book it, use the quote form.