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A building inspection before buying a house is standard practice. But many Auckland buyers overlook the plumbing — and it is one of the most expensive things to get wrong. Here is why a dedicated plumbing inspection is worth every cent.
Why a Building Report Is Not Enough
A general building inspector will note obvious plumbing issues — a dripping tap, visible corrosion, water stains on ceilings. But they will not run a camera through the drains, pressure test the pipes, or assess the age and condition of the hot water cylinder in detail. For that, you need a licensed plumber registered with the Plumbers, Gasfitters and Drainlayers Board.
What a Pre-Purchase Plumbing Inspection Covers
Water Supply
- Water pressure check — adequate pressure throughout the home
- Pipe material assessment — identifying old galvanised steel pipes, lead pipes, or problematic polybutylene
- Checking all taps and mixers for leaks and proper operation
- Toby valve condition and accessibility
Hot Water System
- Age and condition of the hot water cylinder
- Checking for rust, leaks, or signs of imminent failure
- Tempering valve and pressure relief valve condition
- Whether the system meets current safety requirements
Drainage
- Drain flow testing — all fixtures draining correctly
- CCTV camera inspection of main drainage lines (optional but recommended for older properties)
- Checking for root intrusion, pipe cracks, or collapsed sections
- Inspection of drainage under the house and around the property
Gas System
- Checking for gas compliance certificates on file
- Leak testing the gas system
- Condition of gas appliances and connections
- Ventilation of gas appliances
Toilets and Waste Fixtures
- Flush mechanism operation
- Checking for leaks at the base and connections
- Basin, bath, and shower waste operation
What Issues Are Common in Auckland Homes?
Older Suburbs (Pre-1980s)
- Galvanised steel pipes: Common in homes built before the 1970s. Corrode internally, causing low pressure and rusty water. Pipe replacement cost: $5,000 to $15,000+ depending on the extent
- Aging hot water cylinders: Many older homes have cylinders well past their 15 to 20 year lifespan
- Clay drain pipes: Original clay drainage can crack and allow root intrusion — a blocked drain waiting to happen
Newer Homes (1990s–2000s)
- Polybutylene pipes: Some homes built in the 1990s used polybutylene (grey plastic) pipe that is prone to failure — a significant defect to identify
- Leaky building era: Homes from this period may have water ingress issues that have affected plumbing and drainage
What Does a Pre-Purchase Plumbing Inspection Cost?
A thorough plumbing inspection typically costs $250 to $450 depending on the size of the property and whether CCTV drain inspection is included. For a property in the millions, this is an insignificant cost to discover issues that could cost tens of thousands to fix.
Add a CCTV drain inspection for older properties — this costs $200 to $400 more but is highly recommended for homes with mature trees or clay drainage.
Negotiating After the Inspection
If a plumbing inspection reveals significant issues, you have options:
- Request the vendor fix the issues before settlement
- Negotiate a reduction in the purchase price
- Walk away from the purchase (subject to your contract conditions)
- Factor the repair costs into your budget and proceed with full information
Book a Pre-Purchase Plumbing Inspection
Water and Gas Worx carries out pre-purchase plumbing inspections across Auckland. We provide a written report with photos that you can use in negotiations or share with your solicitor. See which areas we service.
Call 0800 322 322 or email service@wgw.co.nz to book.
Frequently Asked Questions
How much does a pre-purchase plumbing inspection cost in Auckland?
A thorough plumbing inspection typically costs $250 to $450 depending on the property size. Add $200 to $400 for a CCTV drain inspection, which is highly recommended for older properties with mature trees or clay drainage. Compared to the cost of discovering major plumbing issues after purchase, it is a small investment.
What plumbing problems should I worry about most when buying an older Auckland home?
The biggest concerns in older homes are galvanised steel pipes (which corrode internally and need full replacement at $5,000 to $15,000+), aging hot water cylinders past their lifespan, and cracked clay drain pipes with root intrusion. A dedicated plumbing inspection will identify all of these.
Is a building inspection enough or do I need a separate plumbing inspection?
A general building inspector will note obvious plumbing issues, but they will not pressure test pipes, assess hot water cylinder condition in detail, or run a camera through drains. For a thorough assessment of the plumbing system, you need a licensed plumber doing a dedicated inspection.
How quickly can you do a pre-purchase plumbing inspection?
We can usually schedule a pre-purchase inspection within a few days. We understand there are often tight timelines around property purchases, so we prioritise these. Call us and we will work with your schedule.