Before you get started

The pipes in the home have many different functions, including water supply, central heating, waste water and gas supply. It is therefore vital to identify the exact function of a pipe before considering work. Never start work if you are unsure of a pipe's function. Never touch gas supply pipes. Always seek professional advice if you are unsure about any pipes.

Copper pipes are traditionally used for all the water supplies, heating pipes and gas supplies in the home. However, plastic pipe is becoming more commonly used for water and heating pipes.

Copper pipes are traditionally connected with soldered joints. However, it is also possible to make joints with compression fittings or copper push-fit fittings. In both these cases there is no need for a blowtorch, flux and solder.

Plastic supply pipes may also be joined with push-fit joints, making them very popular with DIYers. Of the systems available, always check the manufacturer's guidelines on its approved methods of connection, and how joints may be disconnected for adjustment.

Pipe cutters and pipe slices may sometimes be used to cut both copper and plastic pipes. Check packaging for suitability.

Straight coupling joints are shown in this leaflet, but the same jointing principles are applied to elbow joints, tee joints and all the many other joint shapes available.

Most copper and plastic pushfit joints may be used with both copper and plastic pipes.

Most copper and plastic supply pipes are 15mm or 22mm in diameter. However, smaller and larger bore pipes are used, but are less common. Be aware of size differences when choosing joints.

Larger plastic pipes are used for the waste systems in the home. They lead to the underground drainage system.

Waste pipes are connected in three ways. Solvent weld joints use a special cement to make joints; push-fit joints contain rubber ring washers that allow plastic pipes to be pushed in and held, for a watertight join; and compression joints have large plastic rings and washers, assembled to create a watertight joint. The latter are often used around the waste assembly of basins, sinks and baths.

Plastic waste pipes may be cut with a saw, but rough edges must be sanded or filed smooth before any joint is assembled.

Cut pipes

1

Turn supply off if working on water pipes. On copper pipes, mark where to cut and position cutter, remembering pipe ends extend 15mm into a joint.

2

With the pencil mark aligned precisely, tighten the jaws of the cutter by turning the handle. Rotate the tool to begin cutting.

3

After two or three rotations, tighten the handle once more and keep rotating until the pipe cuts in two with a clean, even cut.

4

De-burr the inside cut edge of the pipe, to remove any rough edges, using the de-burring tool that flips out on the back of the pipe cutter.

5

Clean the outside of the pipe with some steel wool to provide a totally clean surface. The pipe is now ready to make a joint.

6

For plastic pipe, the best tool for cutting is a plastic pipe cutter, which has a razor sharp blade that makes a precise, square cut through the pipe.

Make a brass compression joint

1

Disassemble the compression joint and position one nut on each pipe end followed by one olive – these are shaped like gold rings.

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.

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.

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.

Make a push-fit copper joint

1

Push the end of one pipe into the copper joint, which contains a grab ring and seal. Ensure that it goes in as far as possible.

2

Repeat the process with the other pipe, pushing it into the other end of the joint. Again, ensure that the pipe is inserted as far as possible.

3

This is all that is needed unless you need to disassemble and adjust pipe length. Use a demounting tool positioned around the joint collar.

4

Apply pressure on the joint with the demounting tool and this will release the grab ring inside and allow the pipe to slide out.

Make a push-fit plastic joint

1

Position a pipe insert in each cut end of pipe. These stop the pipe ends from distorting when you make the joint. Note the marks on the pipes.

2

Push pipes into the joint as far as possible. The markings on the side of the supply pipes help you gauge how far the pipe is inserted.

3

To lock the joint you may need to twist each side of the joint in opposing directions. This further improves the seal.

4

To disassemble the joint, twist to unlock and apply pressure on the grab-ring collar with one hand while pulling the pipe out with the other.