This is a step by step guide on How to Insulate Water Pipes in your home.  Also known as lagging, pipe insulation helps to prevent heat loss in your hot water pipes. You will be surprised how many houses there are with uninsulated pipes. It is actually one of the easiest and cheapest DIY tasks you can do.

Why Insulate Water Pipes in your Home?

Stop Pipes Freezing Over

This is one of the most important things to consider when you insulate water pipes in your home. It is common to have water pipes running through loft spaces. This is because lofts have vast amounts of open space to run pipes to different regions of your home. If you do have uninsulated water pipes in your loft, then they may be at risk of freezing in the winter months. If pipes freeze then the water inside turns to ice, which expands and eventually bursts the pipe.

Save Money on Heating Bills

Did you know that insulating your water pipes can help raise your hot water pipe temperature by a few degrees? This means better hot water efficiency. You will be surprised the difference this could make to your central heating bills.

Reduce Time for Hot Water Output

Insulating your hot water pipes for taps, showers and baths will slightly reduce the time is takes for your water to run hot. This is because insulation helps keep your pipes warmer for longer. Which means the water in your pipes take longer to cool down.  

Materials Required

15mm, 22mm and 28mm Pipe Insulation

We recommend you buy a good quality, flexible nitrile foam or polyethylene pipe insulation. In general, household copper piping comes in 3 different sizes, being 15mm, 22mm and 28mm. This means you will need to purchase pipe insulation with an internal diameter of these sizes. Typically, you will only need 15mm diameter lagging. You should buy the thickest insulation that your pipes will allow. This is because thicker insulation is more effective then thinner insulation at keeping the heat in. It is common for hot and cold pipes to be close together, which is what will limit the insulation thickness.

You can buy 15mm, 22mm and 28mm pipe lagging from the Amazon store.  They are supplied in 2m lengths.  This type of lagging comes in a sleeved form, which means they have a split so you can push them on to your pipes.

Aluminium Foil Tape

Aluminium foil tape is perfect for taping up the gaps between each piece of pipe insulation.  This is important because heat can easily escape from any gaps in the insulation.

Tools Required

Tape Measure

For measuring the amount of pipe insulation you need in meters.

Long Scissors

The most ideal thing for cutting the pipe insulation. And to cut the aluminium foil tape.

Step 1 – Locate the Hot Pipes

Have a good look around your home for copper pipes. They will usually be hidden out of view, such as in cupboards, around the boiler, near radiators or in your loft. Once you have found some, then work out which pipes are the hot ones. The easiest way to do this is to turn your central heating system on. Those heating system pipes will then be hot to touch. They are the pipes you need to insulate. You can also locate the hot pipes for your taps, shower and bath by turning those on.

Step 2 – Work out How Much Insulation you Need

Once you have gained access to all your hot pipes. You will then need to measure the total meter length of them using a tape measure. Allow an extra 2m for wastage.

Step 3 – Turn off your Hot Water System

Before insulating your pipe work, first make sure you have turned off the central heating system. Otherwise you risk burning yourself on the hot pipes.

Step 4 – Insulate from the Pipe Bends

Pipe bends are typically 90 degrees. In order for the insulation to go round a bend, you must cut a 45 degree in the insulation, each side of the bend. If your bend is less than 90 degrees, then you might be able to bend the insulation around the curve. If you struggle to bend the insulation, then you can cut a small notch in the insulation so that it does bend.

Step 5 – Insulate from the Bends First

Push insulation onto the straight pipes, ensure they are pressed firmly together. When you encounter a pipe clip you can either butt the insulation up against it, then tape the two ends together. Or make a cut at the back off the insulation so that it fits over the pipe clip.

Step 6 – Joining Lengths of Insulation

Join the lengths of insulation together using your aluminium foil tape, making sure they are butted up together before taping them. This will help to trap more heat in. You could also tape along the sleeve opening on each piece of insulation. However, this part is not essential, as the sleeve slits are usually closed tightly.