Velux Windows & Skylights Cambridge

VELUX windows & skylights

A brand synonymous with windows, VELUX is a name you can trust. Known for products that enhance ventilation as well as the amount of natural light in a home, VELUX is constantly innovating and creating the products of the future today.

The team here at Roofing Cambridge has plenty of experience installing VELUX windows and skylights, and can do it quickly and accurately, causing your family or your business minimal disruption.

Skylight & VELUX window repairs

If you already have VELUX products installed in your home but they’ve become damaged, don’t worry, our team can repair them for you. We will carry out an initial assessment to work out whether they can be fixed or require replacing, and then we will get them back in full working order for you.

Here are the different VELUX services that we can offer:

• VELUX window installations
• VELUX window repairs
• Skylight installations
• Skylight repairs

For more information about the different VELUX products that we offer, all you have to do is get in touch. We work throughout Cambridge and the surrounding villages.

New roof windows, replacements and repairs

Replacing an existing roof window

Most older roof windows can be swapped for a new one of the same size, which keeps nearly all the work outside. The old sash and frame come out, the new frame goes in with a flashing kit to suit your tiles or slates, and the lining inside is usually left as it is. It is the simplest way to get better glazing, smoother opening and a watertight roof again.

Fitting a new roof window

A new opening means cutting through the tiles or slates, battens and underlay, and usually trimming a rafter to make the gap the right width. The frame is fixed to the roof timbers, the flashing kit is dressed in around it, and the opening is lined inside. Because rafters are altered, it counts as a structural alteration, and building control normally needs to be involved.

Which type of roof window?

• Centre-pivot. The most common type. The sash turns in the middle, so you can clean the outside glass from inside the room.
• Top-hung. Opens outwards from the top for a clear view and, in suitable sizes, an escape route from a loft room.
• Conservation-style. Low-profile, dark frames with a vertical glazing bar, designed to sit flush in slate roofs on period houses.
• Electric and solar-powered. Handy for windows out of reach; adding an electric opener costs about £300.
• Flat-roof windows and domes. Covered further down this page.

Why is my Velux leaking?

Leaks around roof windows are often blamed on the glass when the real cause is the flashing or a tile above it. These are the usual culprits:

Cause	What you notice	Usual fix (guide price)
Damaged or lifted flashing kit	Drips at the top or sides of the frame in heavy rain	Refit or replace the flashing kit (£180–£500)
Perished seals	Draughts, whistling, water at the sash in driving rain	New seals (£65–£150)
Slipped tiles or debris above the window	Water finding its way round the flashing	Re-fix tiles and clear the head of the flashing
Condensation	Water on the glass and frame inside, worst on cold mornings	Better ventilation and insulation around the lining
Failed double-glazed unit	Misting between the panes	New glazing or a new sash
Rotten timber frame	Soft, stained wood inside	A replacement window

Prices are from Checkatrade’s July 2026 Velux repair guide. We check outside and in before recommending anything. If the problem turns out to be the roof rather than the window, our roof leak repairs page explains how we trace and fix it.

Flat roof rooflights, domes and lanterns

Flat-roofed kitchen extensions are everywhere in Cambridge, and most of them have some kind of rooflight. There are three main types:

• Flat-roof windows: a flat glass unit on a raised kerb, often with a slight fall built in so rain runs off.
• Domes: the traditional moulded rooflight, around £300 to £400 fitted. Old single-skin domes lose a lot of heat and are worth upgrading.
• Roof lanterns: a framed glass structure that brings in light from all sides.

All of them sit on an upstand, and the flat roof covering has to be turned up that upstand and finished neatly under the rooflight’s frame. That junction is where most rooflight leaks start. The best time to upgrade a rooflight is when the flat roof itself is being replaced; see our flat roofing page.

Planning permission, conservation areas and listed buildings

The rules are kinder than many people expect. Under permitted development, a roof window on a house does not need planning permission if it projects no more than 150 mm above the roof slope and is no higher than the ridge. Windows in a side-facing slope must be obscure-glazed and non-opening unless the opening part is more than 1.7 m above the floor.

Greater Cambridge Shared Planning confirms these limits still apply in conservation areas, of which Cambridge has 18. That is different from dormers, which need permission in a conservation area. Even so, the council’s Mill Road appraisal lists “some over-dominant roof lights” among the area’s issues, and the De Freville appraisal notes rooflights inserted into its Victorian slate roofs, so a smaller, flush, conservation-style window is the neighbourly choice on a slope facing the street.

Two exceptions matter. Flats have no permitted development rights for rooflights, so full planning permission is needed. Listed buildings need listed building consent instead. Our guide to planning permission for roofing in Cambridge covers the detail.

How much do Velux windows cost in Cambridge?

Checkatrade’s 2026 cost guides put a complete new roof window installation at about £1,000 to £1,500, replacement of an existing window at £1,000 to £2,500, and repairs at £165 to £1,050. What moves the price:

• New opening or replacement. Cutting a new opening takes more time and timber than a like-for-like swap.
• Size and type. Larger, top-hung and electric windows cost more.
• The roof covering. Slate and tile need different flashing kits, and cutting slates neatly around a frame takes care.
• Access. A loft window on a three-storey house may need scaffold.
• Inside finishing. Lining, plastering and decorating, if they are part of the job.

Our Velux cost and installation guide goes through each line in more detail.

Our roof window process

1. Survey. We look at the window outside and in, by ladder or drone, measure it, check the rafters and the roof covering, and flag any planning points.
2. Written quote. Repair or replacement options, the window type, and exactly what is included inside.
3. Install. The roof is kept watertight at every stage, and the flashing kit is matched to your tiles or slates. Where a window sits near chimneys or valleys, we tie it into the surrounding leadwork.
4. Finish inside. Lining and making good, as agreed in the quote.
5. Hand over. We show you how the window opens and locks, give you photos of the finished work, and put our 5-year warranty on repairs in writing.