Why there is no price list here
Two rooflights that look the same in a brochure can cost very different amounts to fit. One goes into an existing opening on a flat roof with easy access from the garden. The other needs a new opening cut through a slate roof on a steep street, with scaffolding, a trimmed rafter and plastering inside. A price list would be wrong for one of them, and probably both.
So we price each job after a free survey, and we put that price in writing. This page explains what moves the price up or down, so you know what we are looking at when we visit and why the quote reads the way it does.
The unit: type and size
The unit itself is a large part of the price. A sun tunnel, a roof window, a fixed flat rooflight and a roof lantern are different products with different amounts of glass and frame. Within each type, size matters: a larger unit needs a larger pane, a heavier frame and often a stronger kerb.
- Fixed or opening. A fixed rooflight has fewer moving parts and less hardware. An opening unit adds hinges, a sash and a means of opening it.
- Manual or electric. Electric units add a motor, a rain sensor and a controller, plus the wiring to feed them.
- Standard or made to measure. Standard sizes are generally the simpler route. Made-to-measure units suit odd openings and replacements where the old size is no longer made.
- Specialist types. Walk-on rooflights and conservation rooflights are built for particular jobs and are priced accordingly.
The glazing specification
Glass is not one thing. A quote will name the glazing, and the choice changes the price.
- double or triple glazing
- toughened or laminated panes, or both, for safety and security
- solar control coatings that cut heat build-up in south-facing rooms
- self-cleaning coatings on the outer pane
- obscured glass where privacy matters, such as a bathroom
We also look at how the glass unit is held in the frame. A unit that can be changed later without lifting the frame out of the roof can cost more at the start. It usually saves a much larger job years later, and it is one of the things the life plan sets out.
The kerb or upstand
A flat roof rooflight or lantern stands on a kerb, also called an upstand, which lifts it clear of rainwater on the roof. Some units come with their own factory-made kerb. Others sit on a timber kerb built on site. The height, the insulation inside it and the way the roof covering is dressed up its sides all affect the cost. On a replacement, an existing kerb that is sound can sometimes be kept. One that is rotten, too low or the wrong size for the new unit needs rebuilding.
The roof covering
What the roof is made of decides how we open it up and close it again.
- Slate and tile. On a pitched roof we strip back the slates or tiles around the opening, fit the window and its flashing kit, then relay the covering. Old Welsh slate, stone slate and some clay tiles take more care and sometimes matching replacements.
- Felt, single ply, liquid and GRP. On a flat roof the covering has to be cut, dressed up the kerb and sealed. Some coverings are simpler to join than others, and an old or brittle covering may need a wider area of work around the rooflight.
- Metal and other roofs. Standing seam and profiled sheet roofs have their own details and are priced on what the survey finds.
Access and scaffolding
We have to reach the roof safely. A single-storey extension with a clear garden is the simple case. A loft roof window on a three-storey terrace, a roof over a conservatory or a building with no rear access is not. The quote will say what access the job needs. Where scaffolding or an access tower is required, its cost is included in the fixed price, and we tell you how long it will be up.
Structural trimming
A new opening in a pitched roof usually means cutting one or more rafters and trimming around the gap with new timbers that carry the load. A new opening in a flat roof means the same for the joists. How much trimming is needed depends on the unit size, the spacing of the existing timbers and their condition. Where the work changes the structure, we fit to current Building Regulations. On larger openings or unusual roofs, a structural engineer's calculation may be needed, and the quote will say so.
Making good inside
The job is not finished when the roof is watertight. Inside, the opening needs a lining, plasterwork and a neat finish where it meets the ceiling. The quote sets out exactly what making good is included, for example:
- forming and insulating the lining or light well
- plastering or boarding the reveals
- making good the ceiling around the opening
- whether decorating is included or left to you
A deep light well through a loft space to a room below takes more work than a roof window in a sloped bedroom ceiling, and the price reflects that.
Electric, solar and extras
Electric opening units need a power supply, which may mean a new circuit or a spur from an existing one. Solar-powered units avoid the wiring, at a higher unit cost. Rain sensors, remote controls, wall switches and links to a smart home system each add to the price. Blinds, whether manual, electric or solar, are priced as extras, as are insect screens and external awnings where they are made for the unit.
Building Control fees
Replacing a rooflight or roof window in a home is controlled work under the Building Regulations, and so is a new opening that alters the roof structure. Where the work is notifiable, we handle the Building Control notification for you, with the local authority or a registered building control approver. The fee that body charges is set by them, not by us. We include it in the quote as its own line, so you can see it.
Planning permission is a separate question. Most rooflights on houses fall within permitted development, but flats, listed buildings and homes under homes where an Article 4 direction applies (common in conservation areas) are different. If the survey suggests a planning application may be needed, we tell you before you commit.
How our fixed written quote works
After the survey we send a written quote. It is fixed: the price we quote is the price you pay for the work it describes. It sets out:
- the unit, named and sized, and its glazing
- the work on the roof, including the kerb, flashing and roof covering
- any structural work and the access needed
- the making good inside and where it stops
- any Building Control fee, shown separately
- the life plan for the unit
- the payment stages
The price only changes if the work changes. If you ask for something extra, or if opening the roof uncovers a problem that could not be seen at the survey, such as rotten timbers hidden under the covering, we stop, show you, and agree any change in writing before going further.