Skip to content

Pool Pipe Sizing - Very Confusing

We are often asked to help identify the size of pool piping. Here is our guide:

What size is my pool pipe?

Okay, you want some pipe fittings. You've measured your pipe and it looks close to 50mm diameter, so you go and order 50mm fittings, only to find out they are too large. It may appear to be too big, but we find that in many cases it is not the pool shop that has given you the wrong size, read

Why the confusion?

Depending on the class (wall thickness) of the pipe, measurements are all over the place. Originally pipe sizes were based on internal diameters. All fittings were made to glue over the outside of the pipe. As a result, the outside diameter became the critical measurement for pipe sizing. Over time different grades of pipe (and consequently wall thickness) became more popular, so even measuring the internal diameter is inaccurate. The original sizes used and requested have 'stuck' and are now causing confusion, particularly with consumers trying to match pipe & fitting sizes for repairs.

Common pipe sizes used in pools & spas...

The following sizes are for the EXTERNAL diameter of the pipe that goes into the fitting. E.g... if you want to purchase an elbow, and the pipe diameter that the elbow needs to go onto is approximately 48mm, you need to purchase a 40mm elbow. From the below chart, 40mm & 50mm are the most common in swimming pools.
The pipe/fitting size you need to order
Actual size of the pipe
1/2" / 15mm
3/4" / 20mm
1" / 25mm
1.5" / 40mm
2" / 50mm
2.5" / 65mm
Prev Post
Next Post
Someone recently bought a
[time] ago, from [location]

Thanks for subscribing!

This email has been registered!

Shop the look

Choose Options

Edit Option
this is just a warning
Product Enquires
Shopping Cart
0 items

Before you leave...

Take 20% off your first order

20% off

Enter the code below at checkout to get 20% off your first order


Continue Shopping