Short version
Typical UK market figures for a conservation rooflight run from about £1,000 to £2,800 for the unit. These are market figures to start from, not our prices. The final quote depends on size, whether the frame is steel or aluminium, the glazing, the glazing bar, the flashing for your roof covering, and any consent work. The written quote follows the free survey, once those are known.
What the market range is, and what it is not
The figure of £1,000 to £2,800 is a typical UK market range for a conservation rooflight, and it is a starting point rather than a price from us. It describes the unit as the market sells it. It does not describe your roof, your street or your access.
Conservation rooflight cost varies because the product is made to sit flush with the roof covering, in a slim frame, often with a central glazing bar. That detail takes more making than a standard roof window, and the choices below move the figure up or down. Our full cost pages are collected on the costs page, where the other unit types are set out in the same way.
Size and the frame material
Size is the simplest driver. A larger opening needs a bigger frame and a larger glazed area, and in a roof with narrow rafter spacing it may need trimming and support, which adds work. Smaller units suit the gaps between rafters in older houses.
The frame is the next choice. Steel conservation rooflights have a slim, traditional profile that suits period roofs, and they are generally made to order. Aluminium frames are widely used and suit a range of budgets. Our answer on steel conservation rooflights explains the trade-offs, and the guide on conservation rooflight specification covers the rest of the choices.
- Larger opening, larger frame and glass
- Steel frame: slim profile, usually made to order
- Aluminium frame: wide range of finishes and sizes
- Rafter trimming where the opening is wider than the gap
Glazing and the glazing bar
Glazing options affect the cost. A plain double-glazed sealed unit sets the starting level. Moving to three panes, adding a solar control layer, a self-cleaning coating or a laminated inner pane each alters the specification and the figure. Which suits the house depends on the room and its aspect.
A glazing bar, the slim vertical bar that divides the pane, gives the traditional look many conservation areas favour. It is a design choice that affects how the unit is made and what it costs. Our answer on the conservation rooflight glazing bar explains when one is used.
Flashing and the roof covering
A conservation rooflight sits in the plane of the roof, so the flashing has to match the covering around it. Slate, plain clay tile, stone slate and pantile each need a different flashing arrangement, and a heavier or more irregular covering means more careful cutting and finishing.
Access is part of this. A rear slope reached from a garden is quicker to work than a steep front slope in a tight street where scaffold must be arranged. Both are noted at the survey and written into the job plan.
| Driver | What it changes |
|---|---|
| Size | Frame, glass area and any rafter work |
| Steel or aluminium | Profile, finish and lead time |
| Glazing specification | Coatings, extra panes, laminated inner |
| Glazing bar | How the unit is made |
| Roof covering and flashing | Cutting, flashing and finish |
| Access and scaffold | Time on the roof and set-up |
Consent work in a conservation area
Inside a conservation area, a house rooflight can still fall under Class C permitted development unless an Article 4 direction removes that right, and many councils favour flush conservation-style units. Works affecting a listed building need listed building consent. In the Railway Village, Swindon Borough Council has published an Article 4 direction, so the current wording should be checked with the council.
Where consent is needed, preparing drawings and an application is separate work from the unit, and any council fee is paid to the council. Our job is to look up the position on your street and report it in writing; the council decides. The answer on front roof rooflights in conservation areas covers the front slope in more detail.
Where people overspend and underspend
Cost questions usually arrive before the design is settled, which is understandable. The trouble is that a single number quoted too early hides the choices that move it, and the choices are where the useful decisions are made.
The cheapest unit is rarely the cheapest result. A thin specification that suits a bathroom may leave a south-facing bedroom hot in summer, and a swap later means paying for the roof work twice. Equally, adding every option because it is on the menu can push a quote up without improving the room.
A sensible route is to decide the size first, then the frame, then the glazing for the aspect of the room, and only then the extras. Taking the decisions in that order keeps the figure tied to what the room needs.
How we turn the drivers into one quote
The survey is free. We measure the opening, look at the rafters and the covering, and note how the roof is reached. A written quote follows, with a job plan attached, so the figure is tied to a defined job and not a loose estimate. The plan lists the unit, its size, where the permission stands, the route through Building Control, the wait for delivery and the day of the fitting.
If the job is notifiable, we send the notification ourselves, and the fitting is covered by a 10-year workmanship guarantee. Comparing quotes is easiest when each states the frame, the glazing and the flashing, because the same headline unit can come with very different details underneath.
For the overall service, see conservation rooflight installation. A closely related question is how these units compare with a standard roof window, covered in conservation rooflights against VELUX windows.