Waterproofing Inspection: Why This Stage Should Never Be Skipped (Brisbane 2026)

Waterproofing is one of the most critical — and most misunderstood — stages of a new home build.

It happens before tiles go on, when membranes, penetrations, and junctions are exposed and can actually be inspected properly.

Once tiles are installed, waterproofing defects are hidden, and issues often don’t appear until long after handover.

A waterproofing inspection is about catching problems before they’re sealed in.

Why Waterproofing Matters So Much

Waterproofing failures can lead to:

• Water ingress

• Rot and mould

• Tile failure

• Structural damage

• Expensive repairs years later

And unlike cosmetic defects, these issues are rarely simple or cheap to fix once the home is finished.

When Does Waterproofing Stage Occur?

Waterproofing inspections are carried out after:

• Wall linings are installed

• Wet area substrates are prepared

But before:

• Tiles are installed

• Screeds are poured (where applicable)

This is the only time membranes, junctions, and detailing can be visually checked.

What a Waterproofing Inspection Covers

At BSPI Inspections, waterproofing inspections typically focus on:

Wet areas

• Bathrooms

• Ensuites

• Laundries

• Powder rooms (where applicable)

• Balconies (if included)

Common inspection items

• Membrane coverage and continuity

• Floor-to-wall junctions

• Hob and shower recess detailing

• Penetrations (pipes, wastes, mixers)

• Terminations and edge detailing

• Compliance with AS 3740 (where applicable)

Common Waterproofing Defects We See

These are issues we regularly find before tiles go on:

• Incomplete membrane coverage

• Poor detailing around penetrations

• Missing or incorrect bond breakers

• Membrane not returned up walls correctly

• Poor floor waste detailing

• Damage to membrane before tiling

Once tiles are installed, many of these defects are impossible to confirm without removal.

Why Waterproofing Issues Are Often Missed

Waterproofing is usually:

• Covered quickly

• Installed under time pressure

• Rarely seen by homeowners

• Signed off before tiles hide everything

By the time problems show up, the damage is often already done.

How Waterproofing Links to Fixing Stage

Even if waterproofing “passes”, issues can still arise later due to:

• Damage during tiling

• Incorrect tile falls

• Poor junction finishing

That’s why waterproofing inspections and fixing stage inspections work together.

👉 Related guide:
Fixing Stage: Why You Shouldn’t Skip This Inspection
Waterproofing Defects Explained (Video)

In this video, we walk through real-world waterproofing defects found during inspections and explain why they matter before tiles go on.