Choose pipe by the pressure it must carry and what you can get: salvaged plastic or copper pipe where it exists, bored log or bamboo for short low-pressure runs, and fired clay for low-pressure buried lines. Never use lead pipe for drinking water, and keep the static head below the pipe’s limit, which is only about 3.5 to 7 m for bamboo and at most 10.6 m for a bored log.
Pipe materials for a gravity system range from salvaged modern plastic and copper to hand-made bamboo, bored wood and fired clay. Each has a pressure limit, a life and a way of failing, and the choice follows from the head you have.
Match The Material To The Head
Head sets pressure at 0.098 bar per metre (Calculating Head Pressure). The pressure ratings on Pipe Making convert to head as 1 psi ≈ 0.70 m, since 1.42 psi per metre:
| Material | Rated pressure | Head it can take | Life |
|---|---|---|---|
| Bamboo | 5-10 psi | 3.5-7 m | 2-5 years (parent page) |
| Bored log | up to 15 psi | up to 10.6 m, but Wooden Pipes designs for under 3 m | 15-30 years in wet service (parent page) |
| Fired clay | gravity only | Low head; no water hammer | Centuries when laid carefully |
| Salvaged plastic or copper | Set by the pipe’s own rating | Check the rating | Long if buried and kept from sunlight |
| Lead | High | Never for drinking water | Poisons the water |
Where the head is above a material’s limit, break the line with a break pressure tank or choose a stronger pipe.
What Each Is Good For
- Salvaged modern pipe is the best option when it can be found: durable, leak-resistant and with fittings designed for it (Salvaged Modern Pipe).
- Bamboo is fast to make and easy to repair where it grows, but it rots in a few years (Bamboo Pipe Systems).
- Bored log lasts decades if kept wet and buried, but is slow work (Wooden Pipe (Log Boring)).
- Clay lasts longest in the ground but is heavy and breaks under pressure (Clay Pipe).
Rules For Any Pipe
- Keep drinking water pipe clean inside and capped at the ends until laid.
- Slope or arrange it so air can escape at high points (Air Valves).
- Bury it below the frost line or drain it before freezing: 0.5 m in mild areas, 1.5 m or more in severe cold (Winterization).
- Test it with water before burying it, never with air.
- Keep it apart from any non-drinking line (Plumbing Separation).
Common Mistakes
- Using lead, or old pipe of unknown origin, for drinking water.
- Using more head than the pipe’s limit.
- Choosing a short-lived material for a buried line that is hard to dig up.
- Leaving pipes uncovered in sunlight, which damages plastic and dries wooden pipe.
Safety
Lead pipe, contaminated salvage and over-pressure are the hazards
Lead dissolves into water and poisons, especially children; never use it for drinking water. Salvaged pipe may have carried fuel, chemicals or sewage, or may be asbestos-cement; see the checks on the salvaged-pipe page. A line over its pressure rating can burst: never test a line with compressed air.
What’s Next
- Learn next: Salvaged Modern Pipe — the best option, with the checks it needs
- Combine with: Storage Tanks & Cisterns — what the pipe feeds