AS3740-2021 bathroom waterproofing done properly.
Almost every bathroom failure we're called to inspect traces back to bad waterproofing. Our in-house waterproofers apply a two-coat liquid membrane, photograph every step, and issue a certificate signed by the certifier who did the work — not a subcontracted paper trail.
What's included in every bathroom waterproofing.
Every inclusion below is written into your fixed-price contract before work begins. No allowances, no PC sums, no vague line items.
- Substrate inspection and moisture check
- Primer coat on all wet-area surfaces
- Bond-breaker on internal corners
- Two-coat liquid membrane system
- Falls verified to floor waste
- 72-hour cure before tiling
- Photographic record of every coat
- Signed AS3740-2021 certificate
Certified, insured, warranted.
Registered Domestic Builder with licensed trades on staff — no roving subcontractors, no compliance gaps.
- AS3740-2021 compliant
- In-house licensed waterproofers (not subcontracted)
- $20M public liability insurance
- Six-year warranty on membrane workmanship
Bathroom Waterproofing — the honest answers.
Do we need to remove tiles for you to waterproof?
Yes — proper waterproofing sits behind the tile bed. Any 'topical' membrane applied over existing tiles is a temporary bandaid, not a compliant fix.
Will insurance accept your certificate?
Yes. Every certificate is issued in the applicator's name with photographic evidence attached, which is what insurers require for future claims.
Read before you sign a quote.
- 8 min read
AS3740-2021 Waterproofing Explained (Plain English)
What AS3740-2021 actually requires in a Melbourne bathroom, how compliant waterproofing is built up, and how to check a certificate is legitimate.
- 6 min read
How to Diagnose a Shower Leak Before You Strip a Tile
Moisture mapping, silicone tests and hob inspection — how to work out where a shower is actually leaking from.