Water Supply Pipe Replacement Cost

It can feel overwhelming to deal with replacing a main water pipe in your home, as it can come with a lot of upheaval and cost. You may want to replace your water main if you still have lead pipework, your water pressure isn’t very good, or you’ve had lots of leaks.

It’s difficult to say exactly how much water supply pipe replacement costs, but the average cost for 20 metres of pipework is around £750. We’ll go through the factors that can affect the cost in this guide.

How much does it cost to put in a new water line?

How much it costs to put in a new water line will depend on the amount of pipework you need and how difficult it is to access. Since there are so many factors involved, it can be difficult to estimate how much it costs to replace your water supply pipe, but a reasonable cost for 20 metres of pipework would be £750.

Some water companies in the UK will replace your water main for you, which might come at a discounted rate. You can find your local water supplier on Water UK.

Benefits of replacing your main water line

While it might seem like a hassle, there are a few benefits to replacing your main water line:

Increase pressure: Your flow rates should be improved since the pipes will be larger and more flexible

Improve water quality: New plastic pipes won’t contaminate your drinking water

Environmentally friendly: Your pipes will deliver water to your appliances quicker, saving you energy, and you won’t need to use bottled water since your drinking water will be purer

Who is responsible for replacing a water supply pipe?

It’s often wrongly assumed that your water supplier is responsible for repairs to or for replacing your water supply pipe. Generally, your water supplier is responsible for all pipework from the road up to your main stop tap – if you have a meter, it’s usually attached to this – and you are responsible for the pipework that runs into your property from the main stop tap.

Some properties, especially old ones, may have supply pipes running under its entire length. It might be worth looking into special plumbing and drainage cover in addition to your home insurance if you have pipes running under your property, as if there is a leak it could cost a lot of money to locate and repair.

Why should I replace lead water pipes?

If you live in a property that was built more than 50 years ago and you’re unsure if any replacement plumbing work has been carried out, your mains pipes could be made from lead. You can tell whether your pipes are lead by looking at them – if they are a dull grey colour or shiny and silver when you gently scratch the pipe, they’re lead.

It's a good idea to replace lead pipes with modern plastic ones or copper pipes because traces of lead could get into your drinking water. Lead poisoning can cause high blood pressure, memory loss and abdominal pain amongst other symptoms, so it’s worth replacing your lead pipes if you can. However, if you live in a hard water area, there is probably a lot of limescale build-up on your pipes. This will act as some protection from lead getting into your drinking water.

What is involved in replacing a water supply pipe?

Replacing a water supply pipe can be an extensive job and could disrupt your home for a few days. Most of the time, your plumber will replace your water line with plastic piping. There are a couple of common methods used for replacing water pipes: digging trenches and moling.

It's worth remembering that if you need to dig up a public footpath you'll need permission from your local council. Your plumber should be able to help you with this.

Digging trenches

If you only need to replace a small section of water pipe, digging a trench is probably the most cost-effective option. The plumber will excavate the entire length of the pipe that needs replacing before removing it.

In some properties this may be impossible to do, so your plumber will recommend using the moling method.

Moling

Moling involves digging ‘pits’ at measured intervals then driving a torpedo-shaped metal tube through the ground that creates a tunnel under the surface that pipework can be fed through. Depending on how long the pipework needs to be, the plumber may excavate multiple pits to fire the pipework between.

Moling usually costs less than digging trenches because it takes less time and is less labour-intensive. You also won't have to deal with the disruption of having long trenches dug near your home, so it can be a much better option.

How long does it take to replace a water supply pipe?

How long it takes to replace your water supply pipe will depend on how long your pipes are and how easy to access they are. But generally, you can expect it to take between 1-3 days.

Are water supply pipes covered by house insurance?

Generally, the replacement of water supply pipes won’t be covered on house insurance. Most policies will cover you for water damage, often called ‘escape of water’. That means that if your supply pipe leaks and causes damage it will cover the cost of repairing that damage. It rarely covers the cost of repairing or replacing the leak.

You can buy specialist plumbing and drainage cover that would cover the cost of repairing a leak to your supply pipe, and possibly a full replacement of the water line if there were multiple leaks. However, it’s unlikely that the policy would cover you if you wanted to replace your water main as a preventative measure or to improve pressure or water quality.

Water supply pipe replacement can be a big job, so we’d recommend getting at least 3 quotes from reputable plumbers to ensure you’re getting the best price and they’re advising you on the best method of replacement for your property. Post your job on HaMuch now to get in touch with trusted plumbers in your area.

Estimates for common plumber jobs;

Rates for other trades