A rooflight quotation is worth very little until somebody has been in your roof space. This page sets out how we get from an enquiry to a fixed price, what moves that price, and what you should expect to see written down before you agree to anything.
Two figures, and the difference between them
The first figure is a range, and you can have one by email within a day or so of asking. It is built from the covering, the pitch, the room and the size of unit you are after, and it will be wide enough to be honest: roughly what this kind of job costs on roughly this kind of house.
The second figure is a fixed price, and it follows a survey. It does not move afterwards unless you change what you have asked for, or unless the roof turns out to be concealing something nobody could have seen at survey. Where that happens you are told before any further work is done, with the cost of it, in writing.
Be wary of a fixed price offered without a survey. It is either padded to cover the unknowns, or it is going to change once the ceiling is open. Neither is what you want.
What actually moves the price
Almost none of it is the glass. A unit is a catalogue item with a published price, and any installer can order the same one.
What moves a quotation is the work around the opening. Whether the rafters can be trimmed between or need a designed alteration. Whether the existing roof build-up has a vapour control layer or needs one introduced. Whether the covering can be lifted and re-laid or has become brittle with age. How the perimeter is flashed, which is a different job on stone slate than on concrete tile. Whether scaffolding is needed or a tower will reach. Whether the room below is finished and needs protecting and making good.
Those are the reasons two houses on the same street get different numbers for the same product, and the reason a survey is not a sales visit.
What your quotation will show
The unit, named by manufacturer and model, with the glazing specification and the U-value written out rather than implied. The structural work, described. The perimeter detailing, including the upstand and the flashing method for your covering. Access arrangements. Making good internally, and to what standard. The programme, in days, including how long the roof is open. What is excluded. The 10-year workmanship guarantee, and what it covers.
If a quotation you are comparing does not show those things, it is not a cheaper version of the same job. It is an incomplete description of a different one.
How long the roof is open
This worries people more than cost does, and reasonably. A straightforward roof window into a tiled pitched roof is usually open and closed within a single working day. Larger openings and lantern installations take longer, and the roof is made weathertight at the end of each day rather than left relying on a sheet. The programme in your quotation says which of those your job is.
Getting started
Use the form on this page. Tell us where the building is, what the roof is covered with, which room you are trying to light, and whether the building is listed or in a conservation area. That is enough for the first figure. The rest follows a survey.
Four steps, no surprises
Survey
We look at the roof, the covering and the slope before we say anything about price.
Specification
The right unit and glazing for that roof and that orientation, in plain terms.
Fixed quote
Written, itemised and firm. The number does not move once work starts.
Install
Opening formed, unit set and weathered, covering made good. Notification is ours.
Tell us about your roof
We start with the building, the covering and the slope. Then we tell you what will suit it, and what it will cost, as a fixed written number.
- Surveyed before it is priced
- 10-year workmanship guarantee
- Building Control notification handled
- New installations and replacements