Which Poly Pipe Do I Need?
UK Flow Centre buying guide
Choose poly pipe by the job, not the colour
Blue MDPE and black irrigation poly do different jobs. Start with what the pipe must supply, then check flow, distance, pressure and the exact fitting system.
1. Start with the water use
2. Select the pipe size around the run
- Smaller pipe can suit short, lower-demand runs.
- Larger pipe becomes more important as the distance, flow demand or number of outlets increases.
- Do not choose from the pump outlet alone: an undersized long run can lose useful pressure before it reaches the far end.
What not to assume: blue and black pipe are not interchangeable just because their outside diameter looks similar. Confirm the intended use, pressure rating and matching fitting system.
3. Coils or straight lengths?
- Coils: good for continuous, curved or buried runs with fewer joins.
- Straight lengths: useful for neat visible pipework, manifolds and supported installations.
4. Build the complete run
Plan the start connection, isolation valve, tees or branches, threaded transitions, end closure and any pressure or filtration requirements before ordering. Fittings need to match the outside diameter of the pipe—not a guessed nominal size.
Quick choice
- Water supply to a tank, building or outlet: start with blue MDPE and matching compression fittings.
- Garden or landscape irrigation: start with black irrigation poly, then size it around the proposed flow and run length.
- Dripline or micro irrigation: use our dripline guide; the final connection may need filtration and pressure control.
- Existing pipework: measure the outside diameter and send a photo before ordering replacements.
Shop water and irrigation pipe
Technical guidance from UK Flow Centre, operated by JK Irrigation Ltd.