Pipes are vital when it comes to creating a consistent, fully-functional water system within your home. Fittings – accessories designed to hold these pipes more securely, are also incredibly important. The best way to ensure all these products work in tandem and maximise their lifespan is to connect them properly.

But how is this done? Pipes themselves can be daunting when it comes to installation, especially with all the more minute processes involved. It doesn’t help to calm nerves knowing the importance of getting it right – installing them incorrectly can lead to leaks, spillages, and other issues that could potentially damage your home in several ways.

This guide has been designed to help you figure out how best to connect your pipes and fittings, covering some of the basics including pipe bending and cutting as well as the connection process itself*.

The good news about piping is that the majority of systems in place today are fairly limited in terms of structural diversity – in other words, there are only a few ways pipes today are built in terms of size and material, making it easier for even relatively inexperienced homeowners to identify the different components that make up their plumbing.

For many years, most plumbing systems consisted of pipes constructed from materials such as iron and lead, and while these can still be found in older homes, modern installations will utilise copper pipes for water and plastic pipes for waste. The majority of these copper pipes possess an outer diameter of 15mm, though there are smaller variations of around 10mm outer diameter for some taps and radiators. Meanwhile, some baths, tanks and boilers will be fed by larger pipe sizes of 22mm and 28mm.

How these pipes are measured may also vary depending on the installation date, with pre-1970s installations likely using imperial dimensions. These will usually consist of pipe sizes measuring 1/2, 3/4, and 1-inch inner diameters, so there isn’t much overall change to sizes. You can easily join a modernised 15mm pipe piece to a 1/2 inch imperial using standard metric compression fittings.

There are exceptions to the simplicity of this compatibility. 22mm pipes cannot connect to 3/4 inch pipes without a 22mm compression fitting featuring a specialised oversized olive. For soldered joints, you can use metric/imperial connectors in the appropriate size dimensions.

There are several ways to cut pipes, though some methods are more effective than others. One common way is with a hacksaw - by simply wrapping masking tape around the pipe as a cutting guide and aligning its edges to ensure a square cut. However, this is far from the easiest or most effective way.

A much more efficient way to cut your pipes is with a specialised pipe cutter. The process can be finished in just a few simple steps:

1. Measure the length of pipe you need for your project and mark it with a pencil. You can then place the cutter over the pipe, aligning the wheel mechanism with the mark you have made.
2. Rotate the pipe cutter around the pipe length, gradually tightening the screw until you successfully cut through the pipe.
3. Remove the burr around the inside of the pipe’s severed end by applying the cutter’s triangular reamer and slowly rotating it.You will need to ensure that no more copper fragments remain in the pipe, as they could potentially cause damage to both valve and tap components.
4. Use wire wool to burnish the outside of the pipe, which will give it a good clean. The result will also provide you with a decent surface for the joint, as well as offer a watertight seal.

There are also multiple ways to bend plastic pipes. If all you need are a couple of gentle curves, then it is possible to do this by hand. However, for more precise bends, we would recommend utilising a bending spring. This mechanism is able to support the internal structure of the pipe, considerably reducing the risk of kinking. 

To use a bending spring:

1. Cover the spring in a coating of petroleum jelly and ease it into the pipe. If the is away from the edge of the pipe, you’ll want to tie a length of cord around the spring.

2. Bend the pipe over your knee, making sure to over-bend it slightly. Also be sure to use a pad of cloth as a cushion to make the process a little more comfortable. 

3. Check that the angle is roughly correct, and then pull the spring from the pipe.

4. If you cannot access the end of the spring to pull it free, try inserting a screwdriver into the eye of the spring and turning it. This should tighten up the spring coils, which in turn should make it easier to remove.

However, these products require a great deal of strength to use efficiently. This is why you may prefer a bending machine, a more modern and efficient method of getting your pipes to bend, especially if they are of a larger diameter. To use, simply:

1. Place your chosen pipe length on the curved former under the pipe stop. Your pipe bending machine will likely possess multiple sizes from which you can choose the correct option to align with your pipe dimensions.

2. Apply the straight former between the pipe piece and the roller mechanism. This should prepare your bending machine for operation.

3. Draw the handles of your pipe bending machine together, which will bend the pipe length in the process. You’ll want to try to overbend it rather than bend too loosely, as copper pipes tend to spring back into shape a little.

The main way to connect cutter pipes has traditionally been via capillary joints that require effective soldering alongside compression joints that can be tightened with an adjustable spanner. Nowadays, plastic push-fit joints are also on the market, and these can be just as effective to use, as well as much simpler to apply. Ideal for professionals and beginners alike. They work with both plastic and copper pipes, and usually, come complete with rubber O-rings for effective sealing.

Before you start – remember that plastic push-fit joints on copper pipes have the tendency to break the continuity of a plumbing system’s earth bonding. This must be restored, a process which can be completed by joining the two copper pipes with a length of 4mm2 single-core earth cable. It can then be secured with earth clamps.

With this said, here is a rundown on how the various types of pipe connections are applied:

In order to connect capillary joints, you’ll need to check the specific type of the joint.

• End-feed should be brushed with a chemical cleaner known as flux onto the pipe end and inside the joint before heating. Add lead-free solder to the mouth of each joint as it’s heated with your blowtorch. The pipe should be flushed thoroughly after joining to remove all traces of corrosive chemical flux.
• Solder-ring joints should be brushed with a chemical cleaner known as flux onto the pipe end and inside the joint before heating. Only heating is needed for these joints. The pipe should be flushed thoroughly after joining to remove all traces of corrosive chemical flux.

1. To connect compression joints, squeeze the specialised metal ring known as an ‘olive’ between the pipe and the body of the fitting.
2.  Then, apply a cap nut by screwing it onto the end of the joint, which provides the necessary pressure against the olive piece. 
3. You'll then want to wrap about five rotations of PTFE tape clockwise around the threads of the fitting, after which you can tighten the cap nut with an adjustable spanner. Do this while holding the fitting firmly with a pipe wrench or water pump pliers – either will do the job.

1. Push-fit joints should be applied by first making sure that your pipe ends are cut cleanly. This means that you cannot use a hacksaw for any cutting. The process must be carried out using a pipe cutter.
2. Mark the depth of the joint on the cut ends of your pipe length before pushing them fully home and pill the fitting to test that it is fully secure. 
3. The metal teeth of the piece can cut into plastic and cause leaks, so you will need to use a specialised protective insert when working with plastic piping.

Connecting pipes is sure to prove valuable knowledge for any would-be DIY enthusiast or homeowner. Contrary to popular belief, it is not solely a job for professionals, though if you feel as though you would benefit from consulting one for advice or assistance, then you should absolutely do so.

*Please note that this set of instructions applies to water pipes – it is highly advised that you don’t attempt to work on gas pipes yourself. Please contact a professional for assistance if you are looking to carry out work on your gas pipes in any way, shape, or form.

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*Please note that this set of instructions applies to water pipes – it is highly advised that you don’t attempt to work on gas pipes yourself. Please contact a professional for assistance if you are looking to carry out work on your gas pipes in any way, shape, or form.