Waste pipe compression fittings are very useful as they can be used to connect solvent weld pipe to push fit waste pipe. Many people struggle with connecting waste pipes as there is a large difference between the outside diameter of a 32mm solvent weld pipe and a 32mm push fit pipe. Because the compression waste fitting uses a tapered washer it can be used on either of the two pipes even with the couple of MM difference between the two. 40mm solvent weld pipe and 40mm push fit pipe also has a large difference between the two different types of pipe, but this is easily rectified by using a 40mm compression fitting.


waste pipe

Here we have two pieces of waste pipe, these are both 32mm but one is solvent weld and the other is push fit. To join these together we will be using a compression fitting. 32mm pipe is normally used for basins, 40mm pipe is normally used for kitchen sinks and baths.

compression waste fitting

We will be using this compression waste pipe bend to join the push fit pipe to the solvent weld pipe. You can use a compression waste to connect any combination of solvent weld or push fit pipe together.

compression fitting nut

Ensure that the pipe is cut squarely and has been de-burred. Slide the compression nut down the pipe facing the direction shown.

compression fitting nut and seal

Now slide the washer down the pipe, it does not matter which way around this washer faces.

tapered washer

This is the tapered washer, this needs sliding on the pipe next and must face the direction shown.

insert pipe in fitting

Insert the waste pipe into the compression fitting body and push the pipe all the way to the pipe stop, check that the tapered washer is not twisted, then slide the compression nut and washer up and start the nut on the threads.

tighten nut

Now tighten the nut in a clockwise direction ensuring that the nut is not cross threaded.

connect solvent weld to push fit

Repeat the process with the other pipe and you have successfully completed a compression waste joint.

 As with any waste pipe the joined pipe must be supported sufficiently using pipe clips to prevent the pipe from sagging.

Push fit waste pipe  Solvent weld waste pipe