Short answer
A VELUX window has no single price, because the size code, the glazing, the way it opens, the flashing, the blind and the work inside each add to the total. We price it after a free survey and put it in a fixed written quote. A like-for-like swap costs less effort than a new opening.
- 10-year workmanship guarantee
- We handle the Building Control notification where notifiable
The size code
VELUX lists each roof window size by code with its width and height. For example, MK04 is 78 x 98 cm, MK06 is 78 x 118 cm and UK04 is 134 x 98 cm. The metal type sign sits on the top edge of the sash, and it shows when the sash is swung open. Any VELUX window made after 1968 carries one.
That code on the sign gives you the window's width and height. A bigger size means a bigger unit and a bigger flashing, and a replacement in the same size slips into the existing gap more easily. Our page on VELUX size codes reads the sign with you.
How it opens and what powers it
A manual window is the simple version. VELUX also makes solar and electric (INTEGRA) windows, and says an integrated rain sensor closes them automatically in the rain. That sensor is VELUX's, fitted on those windows only. An electric window needs a power supply, so the job grows with the model.
A flat roof dome and a low-pitch window are different products again. VELUX says it designed its flat roof dome for pitches of 0 to 15 degrees, and that its low-pitch roof window is for pitches of 10 to 20 degrees. The pitch of your roof narrows the choice before price comes into it.
Glazing options
The glazing list from VELUX includes a dirt-repellent easy-to-clean coating, safety lamination, which VELUX says stops a broken inner pane coming down into the room, and a rain noise reduction option. What a particular window offers varies with the model and the glazing variant, so ask about the glazing at the survey and do not assume it.
In Wales the energy guidance says a new or replacement roof window should have a U-value no worse than 1.4 W/m²K, or a Window Energy Rating of Band B. Our energy-efficient rooflights page covers the glazing side in more depth.
Flashing, covering and access
The window is sealed into the roof with a flashing, and the covering around it decides the work. Slate and tiles are worked around the frame in different ways. An old covering can take more attention than a sound one, and getting to a high or awkward slope can add scaffolding to the price.
Our separate pages cover the cost of fitting a VELUX window and, for the wider picture, what a roof window costs. To see the window beside every other product, read what shapes a price in Newport.
Swapping a unit or cutting a new opening
The biggest difference in effort is between a swap and something new. Where an old VELUX is coming out and the new one is the same size, the opening, the lining and much of the plaster stay as they are. The old frame comes off, the new one is set and sealed into the covering, and the inside is made good.
A new opening is a bigger job. Rafters usually have to be cut and trimmed, because the roof structure is altered to make room for the frame. The lining and finishing inside follow. If you are choosing between a swap to a larger size and a fresh opening somewhere else, the survey is where we lay the two side by side, since both involve work you cannot see from the room below.
In Wales, a glass-only replacement in a frame that stays does not count as building work under the energy rules. Our page on new glass alone for a VELUX looks at when that suits.
Inside the room
After the window is in, the opening is lined, insulated and finished, with the ceiling made good around it. For a bedroom in the loft, a blackout blind earns its place by morning. At around five in June the roof glass lets in the dawn, and a blind that closes off the room is the only thing between the sleeper and the sun.
Blinds are a separate choice from the window, so decide on them while the window is being chosen. They can be fitted with the window when you want them.
Rules, then the quote
Fitting a roof window is building work in Wales. Where the work is notifiable, we handle the Building Regulations notification with local authority building control or a registered building control approver. See VELUX and Building Regulations in Wales.
Planning is separate. A roof window can be permitted development on a house inside the limits for the original roof, though a house in a conservation area, a National Park, an Area of Outstanding Natural Beauty or a World Heritage Site needs an application. The planning page explains it. Book the survey through the form or send photographs on WhatsApp on 07880 284133.