Last updated: 2026-10-10
Seepwise arranges toilet waterproofing in Singapore for HDB flats, condos and landed homes, from a single leaking toilet to a full re-waterproof during renovation. The work matters because the toilet is where most inter-floor leaks start: HDB names bathrooms and toilets as the usual source in older flats (HDB).
What happens on the first visit
The first visit checks whether the toilet is already leaking (moisture readings on the ceiling below if accessible, grout and floor-trap condition, tile hollowness) and whether you need a full re-waterproof or a targeted repair. For HDB flats, the specialist confirms whether hacking is involved, because that needs a permit applied for by the renovation contractor.
What proper toilet waterproofing involves
A full job removes the old tiles and screed, prepares the slab, lays a waterproofing membrane across the floor and up the walls, then screeds and re-tiles. Published HDB-flat guides describe the membrane turned up the walls (figures from 150 mm to at least 300 mm are cited) and a ponding test, where the floor traps are blocked and the floor is flooded for a minimum of 24 hours before any tile goes down (guide).
The ponding test is the step most often skipped, and it is the only one that proves the membrane holds before it is buried under tiles.
HDB rules before you hack a toilet floor
Hacking bathroom floors generally needs an HDB renovation permit, applied for by your renovation contractor (Hometrust). New flats carry a 5-year warranty on ceiling leaks, and HDB states it ceases if floor tiles are changed or the waterproofing system is tampered with (HDB). Guides also note that wet-area floor tiles in new flats should not be changed in the first three years (Hometrust). If your flat is still inside those windows, report a leak to HDB before touching the tiles.
Overlay tiles are not waterproofing
Laying new tiles over old ones avoids hacking and the permit, and it is a common renovation shortcut. It does nothing for a membrane that has already failed: water still finds the slab underneath. If the toilet is leaking now, the fix is under the tiles, not on top of them. See hacking vs non-hacking waterproofing.
What is included
- Leak check before quoting
- Permit handled by the renovation contractor for hacking
- Hacking and debris disposal
- New membrane turned up the walls
- Screed laid to fall toward the floor trap
- Ponding test of at least 24 hours
- Re-tiling (quoted separately if you choose new tiles)
- Photo record of each layer before it is covered
Painting over it vs a quick fix vs a proper repair
| DIY | Quick fix | Proper repair | |
|---|---|---|---|
| Membrane | Paint-on sealer | Thin coat, floor only | Full membrane up the walls |
| Ponding test | No | Often skipped | 24 hours minimum |
| HDB permit for hacking | Not applied | Sometimes skipped | Applied by the contractor |
| Fixes an existing leak | No | Sometimes | Yes, the membrane is renewed |
| Evidence for later | None | None | Photos of each layer |
What it costs
Published 2026 ranges per toilet: waterproofing package S$800 to S$2,500; hacking and disposal S$800 to S$1,500 (Triton, PRDT, Hock Star). Full HDB toilet renovations are quoted higher, around S$5,000 to S$8,000 in one 2026 guide (MoneyBees).
Try the cost estimator or read the waterproofing cost guide.
Related guides
- How Much Does Toilet Waterproofing Cost in Singapore (2026)?
- Do You Need an HDB Permit for Toilet Waterproofing?
- What Is a Ponding Test, and Why Does It Matter?
- Is My BTO Leak Covered by HDB's Warranty?
How it is done
- Check. Is it leaking now, and is a full re-waterproof needed?
- Permit and plan. Permit for hacking in HDB flats, schedule agreed.
- Membrane and screed. Old layers out, membrane up the walls, screed to fall.
- Ponding test, then tiles. Flood test for 24 hours or more, then re-tiling.