Different Pipe Materials Used in Plumbing and Sanitary Drainage

Ryan Hofman
Aug 31
3 min read

When it comes to plumbing and sanitary drainage systems, the type of pipe material used plays a major role in durability, performance, cost, and compliance. In Australia, plumbing installations must comply with the National Construction Code (NCC, Volume Three – Plumbing Code of Australia) and the relevant Australian Standards, such as AS/NZS 3500 Plumbing and Drainage. Choosing the right pipe material is not just about cost—it’s also about ensuring your system meets safety, hygiene, and performance requirements.

Common Pipe Materials in Plumbing and Sanitary Drainage

1. PVC-U (Unplasticised Polyvinyl Chloride)

Where it’s used: PVC-U is one of the most common choices for above-ground and below-ground sanitary drainage.
Advantages: Lightweight, corrosion-resistant, easy to cut and join (typically using solvent cement), and cost-effective.
Standards: PVC-U pipes for sanitary drainage are covered under AS/NZS 1260: PVC-U pipes and fittings for drain, waste and vent applications.

2. PP (Polypropylene) & HDPE (High-Density Polyethylene)

Where it’s used: Common in chemical waste systems and for underground drainage. HDPE in particular is also used for pumped pressure sewer systems.
Advantages: Excellent chemical resistance, flexibility, and durability. Fusion welding provides strong joints.
Standards: Referenced under AS/NZS 3500 for compliance, with HDPE pipes specifically tested to AS/NZS 4130: Polyethylene (PE) pipes for pressure applications.

3. Copper

Where it’s used: Traditionally used for water supply systems, but also suitable for some sanitary waste systems in commercial applications.
Advantages: High durability, heat resistance, antimicrobial properties, and long lifespan.
Considerations: More expensive than plastics, can be prone to theft due to scrap value, and requires skilled installation.
Standards: Copper tubes for plumbing are manufactured in accordance with AS 1432: Copper tubes for plumbing, gas-fitting and drainage applications.

4. Cast Iron

Where it’s used: Still found in older buildings and some commercial/industrial sites. Often used for vertical stacks due to its sound-dampening qualities.
Advantages: Strong, fire-resistant, and excellent for noise reduction.
Disadvantages: Heavy, costly, and subject to corrosion if not properly maintained.
Standards: Historically used in accordance with AS/NZS 1199 (now largely superseded in new builds).

5. Stainless Steel

Where it’s used: Premium choice for aggressive environments such as hospitals, food processing facilities, and coastal areas.
Advantages: Highly resistant to corrosion, long service life, and aesthetically neat in exposed applications.
Standards: Stainless steel pipes and tubes are manufactured to AS 1528 and are referenced in specific sanitary and industrial settings.

6. Concrete and Earthenware (Older Systems)

Where it’s used: Common in older Australian sewer systems, but now largely replaced by PVC or HDPE.
Issues: Susceptible to cracking, root intrusion, and leaks over time. Often replaced during refurbishments or when defects are detected via CCTV inspections.

Australian Standards and Compliance

In addition to the material-specific standards listed above, the AS/NZS 3500 series is the key reference for design, installation, and testing of plumbing and drainage in Australia:

AS/NZS 3500.0 – Glossary of terms
AS/NZS 3500.2 – Sanitary plumbing and drainage
AS/NZS 3500.5 – Housing installations

Compliance with these standards ensures that sanitary drainage systems are safe, hygienic, and long-lasting.

Choosing the Right Pipe Material

Selecting the correct pipe depends on:

Building type (residential, commercial, industrial)
Location (above-ground vs underground, coastal vs inland)
Budget (balancing upfront cost with long-term maintenance)
Regulatory compliance (must meet NCC and AS/NZS 3500)

Working with a licensed plumber or drainage consultant ensures your system is compliant and tailored to site-specific needs.