Compression fittings in the world of plumbing are very common. They are a safe way to connect copper pipe without the use of heat making them popular with DIY’ers.

Many different types of valves, tees, connectors and utilities require compression fittings in order to make them water tight and safe. That is why we at Plumberparts have created a simple instruction video for you to follow which you’ll find below.

Compression fittings work by the compression of an ‘olive’ between two tapered surfaces and the pipe itself. The two surfaces are the body of the fitting (be it a valve, connector or any other type) and the nut. Using a spanner and a pair of grips the nut is tightened. This exerts pressure on the olive and bites it onto the pipe.

Compression fittings work well if the pipe is clean and cut properly. Pipeslices are an excellent tool for such a job and are great in tight spaces.

When the pipe has been cut and cleaned, assemble the compression fitting by sliding on the nut and olive at both ends. Hold the compression fitting body tightly with a pair of grips and tighten the nut with a spanner. Its often said in the trade to not over tighten a compression fitting, leaving you more thread in the case of a leak and not distorting the olive or fitting. Generally a nut will need one whole turn after hand tightening.

Often people wrap PTFE round a compression fitting olive to make sure of a water tight seal.