Why You Should Lag Your Pipes

Installing pipe lagging is a great idea for any renovation or new construction project, not only will it save you money on utility bills but it also makes your home safer and warmer by keeping the water flowing through your pipes from freezing and bursting.

Pipe lagging comes in two primary varieties; foam and felt. Which type you select will depend on when installing it and how it will be secured.

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Lagging pipes can help prevent cold water pipes from freezing in places like your loft or attic, as well as reduce noise your pipes make. Not only does this keep your property warmer, but it saves money on heating bills too!

The initial step is to measure your pipes, so you know how much lagging you require. Pipe lagging mainly comes in two varieties, foam or felt; depending on where it will be applied, consult with a local DIY store or plumbing merchant for advice.

Foam lagging is ideal for fitting to existing pipework, or pipes with right-angle ends. It typically comes pre-split along its length and requires minimal cutting to open and slot over your pipe’s length. Once installed, use insulating tape to seal the joint.

To determine the diameter of your pipes, use a tape measure. Most residential pipes are either 15mm, 22mm or 28mm in diameter. You can also check the bore size by inspecting the markings on the outside of your pipe.

Next, measure the wall thickness of your pipe. This will determine how thick a lagging will be around it, and it must correspond to both the bore size and pipe length you measured earlier.

As a general guideline, wall thickness should equal one quarter of the pipe’s diameter. So if your pipe measures 25mm in diameter, then each side needs to have at least 25mm thickness.

Once you’ve taken these measurements, it’s time to shop for your lagging. Most lagging comes in 1m and 2m lengths, so hopefully enough will cover all your pipes.

Your choice of lagging will depend on where it needs to go and the pipes being insulated. Foam lagging is often popular, but not the only choice. If fitting pipes while they’re being installed, felt lagging can also be used; it’s less bulky than foam and usually comes in large rolls.


If your climate is susceptible to freezing temperatures, or any area prone to them, then lagg all your pipes – including central heating pipes and any outside ones connected to water tanks. Lagging helps reduce the likelihood of them bursting, saving you from expensive repairs.

The initial step in laging your pipes is to cut them to size. This can be done several ways depending on the type of lagging and pipe being layed around.

Generally, using a hacksaw rather than a power tool for cutting pipes is preferable. This is because it’s much gentler and requires less force to make an accurate cut, plus, holding the pipe while you work makes cutting much simpler.

You will also need a sharp craft knife to cut your lagging into the correct lengths for each pipe. Most lagging is already split on one side for fitting over the ends of the pipe, so you won’t need to do this yourself (unless the lagging doesn’t come with this split; in which case, you must cut it all the way down one side).

Next, you’ll need a drill to create the holes for your lagging. Generally, one hole should be made per 30cm of material you plan on fitting.

Finally, you’ll need some duct tape to secure the pipe. You can purchase special duct tape designed specifically for laging or use regular duct tape that has been reinforced with rubber adhesive.

This will guarantee the lagging is securely fastened to the pipe, preventing it from shifting or sliding after installation. Additionally, it helps prevent stray lagging from getting caught on anything else, like other pipes.

Before installing your lagging, it’s wise to shut off both hot and cold water and allow the pipes to cool down. Doing this will protect against burning yourself during installation as well as keeping insulation from shrinking too quickly or becoming inadequate.


Lagging your pipes is a cost-effective way to save energy, protect your home against cold weather and save money on water bills. It’s an easy DIY project that will pay for itself quickly if you live in an area prone to cold temperatures.

To begin, measure and mark all of your pipework, particularly any hot water, heating or cold-water pipes located outdoors. Additionally, check the roof of your house for exposed pipes as well as outbuildings like sheds or garages for similar purposes.

Once all pipes have been marked, it’s wise to purchase several different sizes of lagging in order to have enough for all your pipes. There are various types of pipe lagging available, including foam and self-adhesive varieties.

Foam lagging, usually pre-split along its length, works best for fitting existing pipes and can easily be cut to size with a sharp knife. If you need to insulate bends in a pipe, you can makeshift a T-junction by cutting away 45deg pieces from the insulation which joins the top of the bend.

Pipe-wrap can also be used to wrap fittings at corners, sealing them with lagging and taping it with duct tape. Make sure that the duct tape you use has adequate insulation properties so as to prevent the lagging from coming loose once in place.

Some lagging also features a special backing to help keep it secure. This makes it an ideal option for pipes with bends or irregular shapes that may be hard to fit properly.

When laging your pipes, there are a variety of materials you can choose from; one option is recycled wool which has environmental benefits.

Another type of lagging is made from fire-rated material that resists fire and flames. This makes it a great option for any pipework exposed to elements, as it provides extra protection from fire and smoke.


Sealing pipes is an easy and cost-effective way to protect them from damage, burst or leaks. Not only is this simple task easy to complete, but it could save you money in the long run as well.

Pipe insulation comes in many varieties, but two of the most popular are foam and rubber. You can buy either of them from DIY stores or online; just be sure to look for a product specifically cut to fit around your pipes.

Foam pipe insulation usually comes in a roll and has been pre-cut with a slit so you can easily fit it over a pipe. It’s suitable for most applications, making it an excellent choice for hot water pipes since it can withstand higher temperatures.

Alternatively, you can purchase an insulated pipe sleeve to fit over your pipe. These are readily available in DIY and hardware stores and can be used for various applications.

A sleeve is an effective way to protect a leaky pipe, though it must be fitted over part of the damaged portion. You’ll also need some electrical tape or wire ties to hold in place the insulation.

Another option for sealing a leaky pipe is using a repair sleeve, which consists of an adhesive rubber gasket patch and clamp. This can be purchased from any local hardware store and provides an airtight, watertight seal.

Pipe thread tape is another option; this plastic-based, adhesive material can be wrapped around the joint of a leaky pipe to create a watertight seal. It works on any type of pipe, including those made from metal or plastic.

Pipe thread tape is an affordable and straightforward DIY option – even for novice DIYers! Plus, it’s waterproof and long-lasting so you can rest assured your piping will remain in great condition.

For the more experienced DIYer, PTFE (Perfluorooctanoic Acid) tape may be worth exploring. This non-stick and slippery tape helps lubricate pipe threads during assembly and can also serve as an effective sealant in joints that don’t have a gasket or washer attached.

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