What does a waterproofing warranty usually cover?
Usually the watertightness of the installed membrane for a stated period, on conditions: the system was installed by an approved applicator, the roof is maintained, outlets are kept clear and nobody else penetrates or damages the membrane. Consequential damage, movement cracking and leaks from other sources are often excluded. Read the terms, keep maintenance records and get written consent before any other trade drills through the roof.
From the RRD Field Guide, checked against the sources cited in Flat Roof and Wet-Area Waterproofing in Singapore: Membranes, Ponding, Leak Tracing and Repair. General information, not advice for your project.
The fuller picture
Most flat-roof and bathroom leaks in Singapore come from failed membrane details, not the open field: upturns, outlets, penetrations and laps. Diagnose before repairing, using a controlled flood (ponding) test, moisture mapping and inspection. The code of practice is SS 637:2018. In strata buildings the roof membrane is common property, so the MCST repairs it.
More questions on this topic
- How long should a waterproofing ponding test last?
- Which is better: torch-on, liquid or cementitious waterproofing?
- Who pays for a roof leak into a top-floor condo unit?
- Can I just coat over my old roof membrane?
- Why does my roof leak only during some storms?
- Do I need BCA approval to redo roof waterproofing?