VELUX & Skylight Installation — London & Surrey
VELUX and skylight installation, leak diagnosis and flashing repairs across London & Surrey. Most skylight leaks come down to junction and flashing detail rather than the window itself — which is exactly where roofing expertise matters.
VELUX & skylight services
Proper skylight installation and leak repairs with correct flashing, lead work and surrounding tile or slate details. Done right first time, no repeat visits.
Why most VELUX and skylight leaks come from the flashing, not the window
The VELUX window unit itself — the frame, glazing and seals — rarely fails in normal residential use. What fails is the junction between the window frame and the surrounding roof covering. This can happen because:
- The lead or aluminium flashing kit was not installed with enough overlap at the head and sides
- The surrounding tiles or slates were not cut and bedded correctly around the frame
- Movement over time has opened a gap where the upstand meets the tile edge
- An old felt-only installation — without lead flashing — has now deteriorated
- A previous repair used sealant rather than properly reinstating the flashing, which has since failed
Diagnosing a VELUX leak correctly means getting onto the roof and checking the full perimeter of the window — not just the area directly above where water is appearing inside.
New installation — what good VELUX fitting actually includes
When we install a new VELUX or skylight, the process goes well beyond placing the unit and fixing it down. A properly installed roof window requires:
- Correct structural opening — rafters trimmed and headed to the right dimensions for the window size
- Underlay lapped correctly into the window's own underlay collar
- Flashing kit installed to manufacturer specification — lead or aluminium at the correct code, properly overlapped at all corners
- Surrounding tiles or slates cut and integrated so water is shed positively away from the frame perimeter
- Any new or replacement internal reveal and lining finished cleanly
We include VELUX installation as part of wider roofing projects — roof replacements, dormer work and partial re-roofs — as well as standalone fitting where a property has clear access.
Replacing an old or failed skylight
On properties with existing skylights that are past their useful life, replacement is often the better option compared with ongoing repairs to the flashing. Older skylights — particularly those with aluminium frames or original felt-only flashings — can be replaced with modern VELUX units that carry a manufacturer guarantee and include a proper integrated flashing kit. We assess whether repair or replacement represents better long-term value before recommending a scope.
FAQs
My VELUX window is leaking — is it the window or the roof?
In almost all cases it is the junction detail and flashing rather than the window itself. The VELUX unit's own seals and glazing are generally reliable. The vulnerable area is the perimeter — where the flashing kit meets the tile edge and where water can get behind an improperly fitted or deteriorated upstand. We diagnose which element is actually failing before recommending a fix, which prevents the common situation of replacing the window when the issue was the surrounding detail.
Can VELUX windows be installed as a standalone job, or only during a re-roof?
Both. We install new VELUX windows as standalone projects where a property has suitable access. If the roof is already being replaced, including a new skylight at the same time is the most cost-effective approach — the scaffold, stripped roof and access are all already in place. We will advise on the most practical sequencing for your specific project.
Do you work on all VELUX models, or only specific ones?
We work with the standard VELUX range of centre-pivot and top-hung roof windows, plus the associated flashing kits for plain tile, slate and profiled tile roofs. For unusual glazing or heritage skylights, we can advise on the appropriate approach at enquiry stage.
Related roofing services
- Roof Replacement — full and partial re-roofs across London & Surrey
- Roof Repairs & Leak Fixes — permanent remedial repairs for recurring leaks
- Flat Roof Replacement (EPDM / GRP) — extensions, garages and flat-roof conversions
- Chimney Repairs & Leadwork — repointing, flashing, valleys and lead details
- Emergency Roof Repair — make-safe work after storm damage or sudden leaks
- Fascias, Soffits & Guttering — roofline replacement and guttering installation
VELUX and skylight installation across Surrey and London
We install new VELUX roof windows and repair leaking skylights across Surrey and London — whether as part of a wider re-roof project, where new skylights are being added during a full replacement, or as standalone work where a skylight is leaking or needs replacing. The quality of the flashing kit and surrounding tile integration is what determines whether a roof window stays watertight for years or becomes a recurring problem. Written quote, fully insured, minimum job value £1,000.
Call 01344 558 785 or use our contact page to discuss a new VELUX installation or an existing skylight that is leaking. If you are not sure whether the issue is the window or the surrounding flashing, photos of both the internal staining and the external perimeter help us advise before visiting.