Short answer
Broad UK market figures (a place to begin, and not our prices) put a VELUX like-for-like replacement at about £600 to £1,500 and a roof window in general at about £700 to £1,800. Where a job lands depends on the size code, how the window opens, the glazing, the flashing kit and whether it is a swap or a new opening. Our written quote follows the survey.
What a VELUX window costs, as a starting point
The ranges below are broad figures from across the UK market. Treat them as a place to begin, not as what we charge. A like-for-like VELUX replacement commonly sits between £600 and £1,500, and a roof window overall between £700 and £1,800. They are broad because the jobs behind them differ so much. A small manual swap and a large electric unit in a new opening do not belong in the same bracket.
We do not quote from a range. Once we have been to the house, the written quote gives a figure for your roof, with the unit and the work itemised in the job plan. You read it before committing to the work. The wider picture of costs is on our costs page.
| Job | Typical market range |
|---|---|
| VELUX like-for-like replacement | £600 to £1,500 |
| Roof window, general | £700 to £1,800 |
Size code and the VELUX window cost
The size is the first driver. Read the code as width then height: the letter gives the width, the digits give the height, so a larger pair means a bigger unit with more glass, a bigger frame and a bigger flashing kit. The code is stamped on the data plate on the window, and our guide to reading the code plate shows where to find it.
Size also affects the work around the window. A wider unit may be wider than the gap between rafters, and then the roof needs framing for it. That is labour, not just product, and it is one reason a bigger window costs more than the glass alone suggests.
Manual, electric or solar
How the window opens matters. A manual unit is opened by hand from a handle, usually at the top or bottom. An electric unit has a motor and needs a power feed, a control and wiring, which adds both product and labour. A solar unit has its own panel and battery, so it needs no mains cable, but it still costs more than a manual unit.
Electric and solar models also tend to need more care at the planning stage, because the cable route or the panel position has to be decided before the unit is ordered. That goes in the job plan. For a sense of what the electric end of the market looks like, the electric opening rooflight service covers the wiring involved.
Glazing and flashing type
The glass specification changes the price. Standard double glazing, a laminated inner pane, a toughened or acoustic option and an energy-saving coating each carry a different cost. A roof window going into an existing home has to meet the Part L window limit, which is Window Energy Rating Band B or 1.4 W/m²K, so the glazing is chosen with that in mind rather than as an afterthought.
The flashing kit is a quieter cost. Each kit is made for a roof covering, such as slate, plain tile or concrete tile, and for a position, a single window or a group. A kit for a flat concrete tile is not the one for a slate roof. Our guide to VELUX flashing kits explains which suits which.
We would rather name the kit in the plan than leave it as an extra on the day.
- Size code: width and height of the unit
- Opening type: manual, electric or solar
- Glazing: standard, laminated, acoustic or coated
- Flashing kit for the roof covering
- Internal lining and finish
A swap versus a new opening
The biggest single factor is whether the opening already exists. Swapping a window for the same size, in the same place, is the simplest job: the roof structure is unchanged and the work is mainly removing and refitting. A new opening means cutting the roof, trimming rafters if needed, framing the opening, flashing and lining the inside. More hours, more materials and often scaffold.
If you are replacing a VELUX in an existing opening, our replacement guide sets out the steps. For anything involving a bigger or new opening, the survey decides, because the rafters and the roof covering decide how much work the opening needs.
Lead time, access and the finish inside
Three smaller items sit beside the unit and the roof work. Ordering takes time, so the lead time is set by the model and size, and an unusual size or a special glazing can take longer than a stock one. Access matters too: scaffold on a taller house, or a long carry to a loft with a narrow hatch, adds time on the day.
Then there is the finish inside. Where the loft is lined already, plasterwork around the new frame is made good. A bare loft gets its lining as part of the conversion. Neither is a surprise if the survey has looked at it, and each gets its own line in the quote, so the money can be followed.
For the timing of the fitting day itself, see the fitting-day schedule.
How the quote and job plan show the price
The quote you get from Ridgeway Skylights is accompanied by a job plan on paper: unit, size, planning position for your house, Building Control route, order time and fitting date. The cost is laid out against those rows, so you can see what each choice does to the price.
The survey and the quote are free. If you would like to see how a VELUX figure moves between a manual swap and an electric unit in a new opening, ask for both to be priced on the same plan. For the service itself, see VELUX window installation. VAT is applied as the law requires, and the quote shows it.