Making a compression joint

Making a compression joint to join copper pipes is a very straightforward plumbing task. Although copper pipes are traditionally connected with soldered joints, it is also possible to make joints using compression fittings. There is no need for a blowtorch, flux and solder, therefore making them is a much simpler option for DIY. Making a joint with a straight coupler is shown below, but the same jointing principles are applied to elbow joints, tee joints and all the many other joint shapes available.

Most domestic copper pipes are 15mm or 22mm in diameter – smaller and larger bore pipes are sometimes used but are less common. Be aware of size differences when choosing compression joints and fittings. For information on cutting pipes please see my guide - ‘Cutting copper pipe’. There is also a lot more information on compression joints and fittings in my guide – ‘Plumbing joints’.

Positioning olives for compression joint 1. Disassemble the compression joint and position one nut on each pipe end followed by one olive.
Assembling compression joint body 2. Push the central part of the joint, the joint body, onto the end of one pipe. Slip the olive and nut down towards the thread of the joint.
Tightening compression joint with adjustable spanners 3. Use one adjustable spanner to grip the joint body and another (or slip-joint pliers) to grip the nut. Rotate each tool to tighten.
One to two full turns for compression joint 4. Repeat the process to join the second pipe to the joint body. Nuts should be tight, but do not overtighten. Between one and two full turns should suffice.



Leave a Reply