A client’s recently built rear extension was experiencing severe water leakage due to improper GRP roof installation. Multiple repair attempts failed to resolve the issue, leading to water damage in the lounge below. Our investigation revealed significant problems: ponding water, missing roof decking (insulation was bonded directly to joists), no vapor control layer, and leaking coping stones.
To fix these issues, we implemented a comprehensive solution using a Sikaplan PVC single-ply roof system. The renovation included:
- Installing 18mm OSB SmartPly on the roof base and parapet walls
- Creating proper roof slope for drainage
- Adding a vapor control layer
- Installing 150mm PIR insulation board to meet building regulations
- Extending the Sikaplan membrane over the walls to prevent water penetration
The new installation comes with an insurance-backed guarantee and Sika warranty, providing long-term peace of mind for the client. The existing lanterns were preserved to maintain cost-effectiveness, with the option to update them later.
