Why are there so many types of plastic pipe, and which do I have?
Look under a house or in a cupboard and you might see white, grey, black, blue, red or green plastic pipe. Each is a different material, made for a different job: drainage, cold water, hot water or gas. They've come and gone over the decades, so older homes can have a mix. Here's a plain guide to the common ones and how to tell them apart. If you're not sure, we can identify yours.
The common types
PVC (drainage)
Rigid white or grey pipe used for sewer, waste and stormwater. Joined with solvent cement. Not for pressure water inside the house.
Polyethylene (poly)
Black pipe, often with a blue or cream stripe, used for water services from the meter, irrigation and underground lines.
PEX
Flexible pipe, often white, clear, red or blue, used for hot and cold water inside homes. Joined with crimp or expansion fittings.
Multilayer (PEX-AL-PEX)
Plastic with an aluminium layer inside, which holds its shape. Used for water, and certified versions for gas, often yellow. See PEX gas pipe.
Polybutylene
Flexible pipe, often grey, used for hot and cold water in some homes. See grey polybutylene pipe.
Polypropylene (PP-R)
Usually green, joined by heat fusion. Used for hot and cold water.
Why so many?
Each material suits different jobs: drainage needs rigid pipe, hot water needs heat resistance, underground services need toughness. Manufacturers have also improved materials over time, and homes plumbed in different decades used whatever was standard then. Repairs and extensions add more types to the mix.
How to tell what you have
- Look for printing along the pipe: brand, material code (PVC, PE, PEX, PB, PP-R) and pressure rating.
- Note the colour and whether it's rigid or flexible.
- Look at the fittings: glued, crimped, brass compression or heat-fused.
- Take photos and send them to us, or we can check on site.
Why it matters
Different pipes need different fittings and repair methods. Mixing the wrong fittings causes leaks. Knowing what you have also helps when buying or selling, or if a particular product has a known issue. We repair and replace all common types, with a fixed price before any work starts.
Why locals call us
- Local to Matraville and the southern Eastern Suburbs
- Free on-site quotes, with a fixed price before any work starts
- Lifetime labour warranty on our workmanship
- 100+ five-star Google reviews
- Licensed plumbers and gasfitters (Lic. 398171C)
Common questions
What is the white plastic pipe under my house?
Usually PVC drainage pipe for waste or sewer, or PEX if it's flexible and carrying water.
What is the grey flexible water pipe in my home?
It could be polybutylene or another plastic. The printing on the pipe tells you the material.
Can different plastic pipes be joined together?
Yes, with the right transition fittings. Using the wrong fittings causes leaks.
Is plastic pipe as good as copper?
Approved plastic pipes installed correctly are reliable. Each material has its own uses and limits.
Related help: grey polybutylene pipe, PEX gas pipe, galvanised pipes guide and leak detection. Local pages: Matraville, Eastgardens, Pagewood and Maroubra. Browse all our plumbing guides.