A professional waterproofing inspection gives you a clear picture of where your home is vulnerable to moisture intrusion, what damage may already exist, and what work is needed to protect it. In New Zealand's varied climate — from the wet West Coast to Auckland's humid summers and Wellington's wind-driven rain — waterproofing is a critical part of keeping a home healthy and structurally sound. Here's what you can expect when a qualified waterproofer visits your property.
What Does a Waterproofing Inspector Actually Look At?
A thorough inspection covers both the interior and exterior of your home. The tradesperson will systematically assess areas where water is most likely to penetrate or pool. Common areas examined include:
- Wet areas — bathrooms, ensuites, laundries, and kitchens, including showers, baths, and floor-to-wall junctions
- Decks and balconies — particularly timber or concrete decks with membrane systems
- Foundations and subfloor spaces — checking for rising damp, pooling water, or inadequate drainage
- Roofs and gutters — looking for failed flashings, blocked downpipes, or ponding water
- Retaining walls and below-ground areas — basements or rooms built into slopes
- External cladding junctions — around windows, doors, and penetrations where the NZ Building Code's Clause E2 (External Moisture) requirements apply
How Does the Inspector Assess Moisture?
A good inspector uses more than just their eyes. You can expect them to use some or all of the following tools and methods:
- Moisture meters — these probe or scan surfaces to detect elevated moisture levels in walls, floors, and framing without always needing to open up linings
- Visual inspection — looking for staining, efflorescence (white salt deposits), mould, cracked or missing grout, failed sealants, and blistering paint
- Tap and probe tests — tapping tiles to identify hollow or debonded areas that may indicate water has got behind the membrane
- Thermal imaging cameras — some inspectors use infrared cameras to detect temperature differences caused by moisture behind linings (not all inspectors carry these, so ask beforehand)
- Water testing — in some cases, a controlled water test may be done on a shower or deck to check for active leaks
The inspector will note findings as they go, often photographing problem areas for the report.
What Standards and Codes Apply?
In New Zealand, waterproofing in wet areas must comply with the NZ Building Code, particularly:
- Clause E3 (Internal Moisture) — covering wet area waterproofing in bathrooms, laundries, and similar spaces
- Clause E2 (External Moisture) — covering the building envelope, cladding, and drainage
BRANZ publishes detailed guidance on waterproofing systems and acceptable solutions. Your inspector should be familiar with these standards and reference them in their findings. For new work or significant repairs, a building consent may be required — always check with your local council, as requirements vary.
What Does the Written Report Include?
After the inspection, you should receive a written report that covers:
| Section | What to Expect |
|---|---|
| Summary of findings | Plain-language overview of issues found |
| Photos | Images of problem areas with annotations |
| Risk rating | Priority level for each issue (e.g. urgent, monitor, low risk) |
| Recommended work | Specific repairs or waterproofing systems suggested |
| Compliance notes | Reference to relevant Building Code clauses or standards |
A quality report gives you something concrete to act on and can also be useful if you're buying or selling a property.
How Long Does an Inspection Take?
For a typical residential home, allow one to three hours depending on the size of the property and the number of areas to assess. Larger homes, those with multiple decks, or properties with suspected significant damage may take longer. Some inspectors charge a flat fee for the inspection; others may offset the cost against any subsequent repair work — ask upfront so there are no surprises.
What Happens After the Inspection?
Once you have the report, the inspector will usually walk you through the findings and answer questions. From there, you can:
- Get a quote for any recommended waterproofing work
- Prioritise repairs based on urgency — active leaks or areas with structural risk should be addressed first
- Check consent requirements with your council for any significant work
- Compare quotes from other qualified waterproofers if needed
For wet area waterproofing that involves plumbing connections, note that any work on pipes or fixtures is restricted work under the Plumbers, Gasfitters, and Drainlayers Act and must be carried out by a licensed tradesperson registered with the Plumbers Gasfitters & Drainlayers Board.
When to Call a Professional
You should arrange a professional waterproofing inspection if you notice:
- Mould or mildew that keeps returning despite cleaning
- Staining on ceilings, walls, or floors near wet areas
- Tiles that sound hollow or grout that is cracking and crumbling
- A musty smell in subfloor spaces or rooms below ground level
- Water marks or damp patches after heavy rain
- You're buying a property and want peace of mind
Don't delay — water damage can escalate quickly, affecting framing, insulation, and indoor air quality. A home with ongoing moisture issues may also fail to meet the Healthy Homes Standards if it's a rental property; more information is available from Tenancy Services.
You can find qualified, local waterproofing professionals on tradedirectory.co.nz to carry out inspections and any follow-up work.
Site Safe
SiteWise
Licensed Building Practitioner (LBP)
