Plumbing pipes are buried in walls and floors for decades. Choosing the right type for each job avoids leaks, rust-coloured water and expensive breakages later. Here is how the four most common pipes compare.
| Pipe | Hot water? | Joints | Best for |
|---|---|---|---|
| CPVC | Yes | Solvent cement | Hot and cold water supply inside the house |
| UPVC | No | Solvent cement | Cold water lines, outdoor lines (UV-resistant grades) |
| PPR | Yes | Heat-fused | Hot and cold supply, especially concealed lines |
| GI (galvanised iron) | Yes | Threaded | Older homes; largely replaced because it corrodes |
CPVC: the common choice for homes
Chlorinated PVC handles hot water from geysers, does not corrode, keeps water clean and is easy to join with solvent cement. It is widely used for all supply lines in modern Indian homes.
UPVC: for cold water
Unplasticised PVC is strong and economical but not meant for hot water. It is often used for cold water lines, from tank to taps, and for outdoor runs in UV-stabilised grades.
PPR: leak-proof joints
Polypropylene random copolymer pipes are joined by melting the pipe and fitting together with a heating tool. The joint becomes a single piece of material, which makes it very reliable for concealed lines.
GI: why it is being replaced
Galvanised iron pipes rust from the inside over time. Rust narrows the bore, reduces water pressure and colours the water. If your house still has old GI lines, replacing them is often worthwhile during renovation.
Drainage pipes are different
Waste and soil lines from bathrooms and kitchens use PVC SWR (soil, waste and rainwater) pipes, which are designed for gravity flow, not pressure.
Plumbing tips
- Pressure test all concealed lines before plastering or tiling.
- Use one pipe system consistently rather than mixing brands within a line.
- Fit isolation valves in every bathroom and kitchen, so one leak does not shut the whole house.
- Insulate long hot water lines to save geyser energy.
Frequently asked questions
Which pipe is best for borewell water?
Plastic pipes such as CPVC, UPVC or PPR resist the minerals in borewell water better than GI.
Are plastic pipes safe for drinking water?
Pipes certified for potable water from reputable brands are designed for drinking water use.