Clay Pipes vs PVC: What’s Under Your House?
If your home was built before the 1980s, there’s a good chance the pipes under your property are made of clay — and they may be past their best.
In Christchurch, older homes often rely on earthenware or vitrified clay drainage pipes, many of which are now showing signs of wear, damage, or full failure. Earthquakes, shifting ground, and tree roots haven’t helped.
So what’s the difference between clay and modern PVC pipes, and how do you know what’s under your home?
Clay Pipes: The Old Standard
Clay pipes were the go-to for decades. They’re made from fired clay and were commonly used in homes up until the 1970s and early 80s. While durable in their time, they have a few well-known issues today:
Brittle & Prone to Cracks – Clay doesn’t flex. Earthquakes, ground movement, and pressure from above can cause cracks or complete breakages.
Shorter Pipe Sections – Clay pipes were laid in short sections, meaning more joints — and joints are where most problems occur.
Tree Root Invasion – Gaps at the joints or cracks allow roots to find their way in, eventually blocking the pipe or splitting it apart.
Hard to Repair – Fixing a broken clay pipe often means digging, replacing, and disturbing surrounding ground or landscaping.
PVC Pipes: The Modern Choice
Polyvinyl chloride (PVC) pipes have become the standard for modern drainage work — and for good reason:
Flexible & Durable – PVC can handle movement and ground pressure much better than clay.
Longer, Fewer Joints – Fewer connection points mean fewer opportunities for leaks or blockages.
Easier to Install & Replace – Faster installation and simpler repairs mean less disruption and lower costs.
Root-Resistant – Tight seals and tough material make it much harder for roots to get in.
How Do I Know What I’ve Got?
Unless you’ve recently had drainage work done, it’s hard to tell just by looking around your property. That’s where a CCTV drain inspection comes in — we send a camera down the pipes to check the condition, materials, and any issues.
You’ll get clear footage, a written report, and expert advice on what (if anything) needs attention. If you’re dealing with recurring blockages, strange smells, or planning a renovation, it’s a smart place to start.
Book a Free Drainage Check
At Enviroflo, we’ve inspected thousands of Christchurch properties — helping homeowners get clarity and access the repairs they’re entitled to. If your home still has its original clay drains and had an EQC claim from the 2010/2011 quakes, you may qualify for a no-cost CCTV survey.
Book Your Free Camera Check or get in touch to see if your property is eligible.
Free survey available to homes with ceramic drains and a previous EQC (now Natural Hazards Commission) claim. Conditions apply.
