Leaking Glass Roof & Skylight Repair
Diagnosis-led repair for leaking skylights, glass canopies, and glass roofs — full sealant removal, substrate preparation, and marine-grade resealing to stop water ingress for the long term.
Stopping the Leak at Its Source — Not Where the Water Drips
A leaking skylight or glass roof causes disproportionate secondary damage relative to its visible size: stained ceilings, ruined plasterwork, damaged electrical conduits, and mould growth in the structural void. The deceptive part of a glass roof leak is that the water often enters metres away from where it drips indoors — travelling along frame members, rafter channels, or glass laps before appearing as a visible drip inside the building. Applying more silicone over the visible joint almost never solves this. The only reliable fix is to trace the water path to its actual entry point, remove all failed sealant, prepare the substrate correctly, and re-seal with structural-grade weatherproofing compounds.
JWE has made leaking skylight and glass roof rectification a specialty. We are the people other contractors call when their standard repair attempts have failed. Our methodology involves systematic water path tracing (using water testing from the outside while a team member observes from inside), full mechanical removal of all existing sealant in the suspect zone — not spot patching over it — substrate preparation with appropriate primers, and re-application of marine-grade structural silicone and aluminium flashing where required. Glass panels are also inspected for hairline cracks that allow water ingress even when the sealant joints appear intact.
Leak Diagnostics First
We trace the water entry path systematically — the visible drip location inside is rarely the same as the water entry point. We find the source before committing to any repair scope.
Full Sealant Removal
We never patch over old sealant. Full mechanical removal, substrate cleaning and priming, then re-application of structural weatherproofing silicone — the only approach that prevents recurrence.
Glass Inspection Included
During every skylight repair, we inspect glass panels for hairline cracks that admit water even through intact sealant joints. Cracks in overhead glass are a safety hazard that we flag immediately.
Specialist Expertise
We Fix What Others Cannot
JWE is regularly called in to rectify glass roof and skylight leaks where other contractors have applied multiple layers of silicone without success. Our diagnosis-first methodology identifies the actual water entry point, not just the visible symptom.
Book a Leak Assessment
Describe the leak location, when it occurs, and how long the problem has existed. We will arrange a site visit with the right equipment to trace and repair the source.
Request a QuoteOr call 012-9820888
Common Leak Causes
- Failed perimeter silicone sealant
- Blocked drainage channels
- Incorrect flashing detail
- Hairline cracks in glass panels
- Glazing tape degradation
Frequently Asked Questions
Why does my skylight only leak in certain weather conditions?
Skylights often only leak under specific wind-driven rain conditions because the water path is often through a joint that only fills when rain is driven horizontally. The sealant may have opened a gap that ordinary vertical rain drains away from, but wind-driven rain pushes water through. This is why proper diagnosis requires water testing from the outside under controlled conditions, not just waiting for the next rain event.
Can you repair a leaking skylight without replacing the glass?
In most cases, yes. The majority of skylight leaks originate at the perimeter sealant joints or flashing connections, not through the glass itself. If the glass is not cracked or delaminated, a full sealant remediation and flashing correction will stop the leak without disturbing the glass. Glass replacement is only required if we find hairline cracks or delamination during our inspection.
How long does a skylight repair typically take?
A standard skylight sealant repair — involving removal of failed sealant and re-application — typically takes 1 to 2 days on site. More complex repairs involving flashing fabrication or glass replacement may take 3 to 5 working days. We provide a detailed scope and timeline in our quotation before work begins.