Two skylights of the same size can cost very different amounts to fit in Brighton & Hove. One sits on a single-storey kitchen roof reached from the garden. The other sits on a butterfly roof four floors up, behind a parapet, above a permit-only street. The unit might be identical. The work around it is not. This page sets out what moves the cost of a skylight or rooflight in the city, so you can see where the money goes before anyone climbs a ladder, and it explains how our free survey turns all of that into one fixed written figure.
The unit you choose
The product is the part people think about first, and it does carry real differences. A roof lantern is a framed structure of several glazed panels and ridge members, so it involves more material and more assembly than a single flat rooflight of the same footprint. A roof window for a pitched roof comes with a flashing kit matched to slate or tile. A walk-on rooflight uses thick laminated glass rated for a load, and it needs a frame and kerb built to carry it. A conservation rooflight is made to sit low in the slope with slim glazing bars, which is a more specialist product than a standard roof window.
Opening matters too. A fixed unit is the simplest. A manual opening rooflight adds hinges, seals and a winding or push mechanism. An electric rooflight adds a motor, a control and usually a rain sensor, and it needs a power supply run to it.
Each service page has its own cost answer if you want the detail for one product:
- What changes the cost of a roof lantern
- What a flat rooflight costs to fit
- The cost of fitting a roof window
- The cost of fitting a VELUX window
- What an electric rooflight costs
- The cost of a walk-on rooflight
- What a conservation rooflight costs
- The cost of a sun tunnel
- Replacing a misted rooflight: what it costs
Size and glass
A bigger rooflight costs more, but not in a straight line. Past a certain size the glass gets heavier, the frame needs to be stiffer, and lifting it onto the roof can need more hands or a hoist. A long flat rooflight may also need a wider opening in the roof, which brings the structure into play (see below).
The glass specification is the other half. Double glazing is the starting point. Triple glazing, solar control coatings, self-cleaning outer panes and laminated inner panes all add to the unit price. Some of these are choices. Others follow from the Part L energy limits that any new or replacement unit must meet. A roof window on a pitch is held to 1.4 W/m²K, or Window Energy Rating band B, and the limit for a flat roof rooflight or a lantern is 2.2 W/m²K. We specify units that meet those limits as a matter of course, and the quote names the glass so you can see what you are paying for.
The roof it goes into
Brighton & Hove has a wide spread of roofs, and each one changes the job:
- Slate pitched roofs on Victorian terraces need careful stripping and re-slating around a roof window, and the flashing has to suit the slate gauge.
- Butterfly roofs hidden behind a front parapet drain to a central valley gutter. A rooflight there has to be placed and flashed so the valley still carries water away.
- Mansard roofs have a steep lower slope and a shallow upper one. Which slope takes the window changes the product and the flashing.
- Flat roofs on rear extensions may be felt, EPDM rubber or GRP. Cutting a new opening means forming an upstand or kerb and dressing the covering back up it properly.
The condition of the roof matters as much as its type. If the timbers around the opening are sound and the covering has life in it, the work stays local. If the felt is tired or the slates are failing, we will tell you at the survey and price any extra work separately, so the rooflight cost stays clear.
The opening and the structure
Replacing an old unit in an existing opening of the same size is usually the simplest structural job. Making a new opening, or enlarging an old one, is different. In a pitched roof it can mean cutting one or more rafters and trimming the opening with new timbers either side. In a flat roof it can mean cutting joists and adding trimmers. The bigger the opening, the more the structure has to be considered, and a larger opening may need calculations before the work can go ahead.
Inside, a new opening in a loft room or a top landing may need a lined reveal, plasterboard, insulation and a finish to the ceiling. People often forget to ask about this part of the cost of a new skylight.
Building Control
Cutting a fresh opening in a roof counts as building work, and so does swapping a complete rooflight or roof window, even like for like. Both are notifiable. Swapping only the sealed glass while the existing frame stays sound falls outside the controlled fittings. When notification is needed we deal with it, through the council or a private registered building control approver, and the cost of that route sits inside the quote. What gets inspected is set out in our Building Regulations guide for skylights and rooflights.
Planning is a separate question. A house can often take a rooflight under permitted development, subject to conditions, but a flat has no permitted development rights, and an Article 4 direction or a listed building changes the picture. Planning or listed building consent fees are set by the authority, not by us. The planning guide for Brighton & Hove sets out when you need to apply.
Getting to the roof
In this city, access is often the largest single item after the unit, and it is the one that varies most between two jobs. These are the usual routes and what each brings with it:
| Route | Typical use | Permissions |
|---|---|---|
| Ladder or roof ladder | Low single-storey roofs | Usually none |
| Rear scaffold | Garden access to a back slope | Neighbour's agreement if it crosses their land |
| Street scaffold or tower | Front roofs, no rear route | Scaffold licence from the highway authority |
| Mobile platform | Short jobs with a clear road | Often a parking bay suspension |
A scaffold on the pavement or road needs a licence from the highway authority, which is Brighton & Hove City Council in the city, or East Sussex or West Sussex County Council further out. On a permit-only street, a van, a skip or a platform may need a parking bay suspended. Both carry a council fee and a lead time that the council sets. We make the applications and the quote shows them as their own lines. How the process runs is explained in how scaffold licences and parking bay suspensions work.
Height adds to the cost in a plain way: a four-storey terrace needs more scaffold, more time to erect it and more time to take it down than a bungalow.
Making good
Once the unit is in, the roof and the room both need finishing. Outside, that means slates or tiles put back and dressed to the flashing, or the flat roof covering taken up the kerb and sealed. Inside, it can mean a new plasterboard reveal, skim, a sill and decoration. Some people want to do the inside decoration themselves. That is fine: the quote says clearly what we finish and what we leave ready for paint.
Taking away the old unit and the waste is part of the job. On a street with no room for a skip, that may mean bagging waste and removing it by van, which ties back to the parking arrangements.
Replacement or new
Skylight replacement in an existing opening tends to cost less than a new skylight, because the structure is already there. That holds when the new unit fits the opening. If you want a bigger unit, or the old opening was formed badly, the job moves closer to a new installation. Replacing a misted or failed rooflight is still notifiable building work, and the new unit has to meet Part L, so a replacement is never just a swap of glass. The misted and failed rooflights page explains how we assess an old unit.
How the free survey and fixed quote work
We do not give prices over the phone for a roof we have not seen, because the access and the roof are where the cost of a skylight in Brighton & Hove is decided. Instead, the first step is a free survey at your property.
- Book the survey Call, message or use the form. Photos of the roof and the room help us prepare.
- We look at the roof and the room We check the covering, the structure, the opening, the room below and the route up from the street or the garden.
- We plan the access We work out which route suits, what permissions it needs and who else in the building has to agree.
- You get a fixed written quote It names the unit, the glass, the work, the Building Control route and the access, with a price for each part.
The figure we write down is fixed for the work it describes. If you later change the brief, such as a bigger unit or an electric opener, we requote in writing before anything changes.
What the quote contains
Every quote carries the access plan: a written page that shows how we will reach the roof, which licences we will apply for, whether the freeholder's consent or a licence for alterations is needed in a converted building, how neighbours will be told, which Building Control route applies, and what all of that costs. It sits beside the line items for the rooflight itself, the structure, the making good and the waste.
The point is that you see the whole cost in one place, including the parts that depend on the council and the building rather than on us. The work is then covered by our 10-year workmanship guarantee.
If you would like a fixed figure for your own roof, book a free survey.
