Hazardous materials
What do lead pipes mean when you are buying a house?
DWI says lead pipework was commonly used to connect homes before 1970, and was then banned. Homes built after 1970 are unlikely to have lead pipes. If you suspect lead, ask the water company to test the kitchen tap. A surveyor sees pipes they can see, not the buried communication pipe.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless a source says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
Where does lead in tap water usually come from?
The Drinking Water Inspectorate says that before 1970 lead pipework was commonly used to connect properties to the mains, and that this use has since been banned. A home built after 1970 is unlikely to have lead pipes. A home built before 1970 may, including pipework that is still underground or inside and has never been replaced. DWI also says lead is not present in the water in the wider public supply network. The usual route into the tap is the building’s own plumbing: lead dissolves into water while it stands in a lead pipe. Older brass fittings and, wrongly, lead solder on drinking-water joints can add lead too.
DWI’s lead page discusses harm. It says exposure should be kept as low as it can be, that infants and children are particularly at risk because lead can affect mental development, and that in adults it may affect kidneys, heart and circulation. That is a reason to test if you suspect lead pipes. It is not a condition rating, and it is not a bill for replacement. The legal standard DWI publishes is 10 micrograms per litre of lead at consumers’ taps. If you want the regulation text, use the standards DWI publishes rather than a contractor’s leaflet.
Which pipe can a surveyor see?
| Pipe | What DWI says |
|---|---|
| Communication pipe | From the main in the street to the outside stop valve. Belongs to the water company. Usually buried. A surveyor does not dig it up. |
| Supply pipe | From the outside stop valve to where water enters the home. The owner’s responsibility. Often buried as well. |
| Internal plumbing to the kitchen tap | The owner’s. This is the part a surveyor might see at a stop tap, in a cupboard, or under a sink. |
DWI suggests buyers ask the surveyor to note the nature of the pipes they can inspect, and to mention lead in particular. That request matches the limit of a Home Survey. Level 1 does not test the services. No level excavates the communication pipe as standard. A sentence that says “no lead seen” means none was seen in the accessible places. It does not clear the buried pipe in the pavement.
What should you ask the water company to do?
DWI says that if you suspect lead pipes you can ask the water company to test the water at the kitchen tap. If they find lead pipes or another lead source, they should give you written advice. That test is the factual step. Looking at a dull grey pipe where the water enters, which DWI describes, can support a suspicion. It does not replace the sample. Running the tap in the morning is a short-term step DWI describes for water that has been standing in the pipe. DWI is clear that this does not remove the need to deal with lead pipework if it is there.
DWI also says that if you replace lead and the company’s communication pipe is lead and could add to the lead in the supply, you should tell the company, because they have a legal duty to replace that communication pipe in that situation. That is a duty on the company for its pipe. It is not a price for the private supply pipe or the plumbing indoors. This guide does not state a replacement cost.
What should you not assume when you negotiate?
- Do not treat “built before 1970” as proof of lead. DWI says such a home may have lead pipes, not that it must.
- Do not treat “built after 1970” as impossible. DWI says it is unlikely. Fittings and later alterations can still introduce lead.
- Do not treat a visual survey as a water sample. Ask the company to test the kitchen tap if you suspect lead.
- Do not invent a replacement price. Get a plumber’s figure for the pipes that are yours, and the company’s position on the communication pipe.
- Do not confuse this with the electrics. An electrical report says nothing about the water pipe.
Common questions
Were lead pipes banned?
DWI says lead pipework was commonly used to connect properties to the mains before 1970, and that this use has since been banned. Older homes that were never modernised can still have lead underground or inside. A ban on new use is not the same as a statement that every old pipe has been removed.
Is a house built after 1970 free of lead pipes?
DWI says a home built after 1970 is unlikely to have lead pipes. Unlikely is not a certificate. If you can see a soft grey pipe, or you are simply unsure, ask the water company to test the kitchen tap rather than relying on the build year.
Is lead put into the water at the treatment works?
DWI says lead is not present in the water in the wider public supply network. The usual problem is lead already in the pipes and fittings at the property, which can dissolve while water stands. Natural lead in groundwater is described as rare in the UK.
Who tests the water?
If you suspect lead pipes, DWI says you can ask your water company to test the water at your kitchen tap. If they find lead pipes or another source, they should give written advice. A surveyor’s look at a visible pipe is not that test.
What is the legal standard for lead?
The standard DWI publishes is 10 micrograms per litre at consumers’ taps. That is a water-quality limit, not a description of your house and not a works price. Use the company’s test result against that standard. Do not guess the concentration from the age of the building.
Can the surveyor see the communication pipe?
Not if it is buried, which it usually is. DWI says the communication pipe, from the main to the outside stop valve, belongs to the water company. The supply pipe into the house is the owner’s. The surveyor reports pipes they can see.
Does running the tap fix lead pipes?
DWI describes flushing as a short-term way to clear water that has been standing in the pipe. It also says lead pipes, if they are there, should be dealt with rather than left. Flushing is not a repair a survey can sign off, and it is not a reason to skip a test.
How much does it cost to replace lead pipes?
This page does not state a cost. Length, access and who owns each section all change the job. Ask a qualified plumber about the private pipework, and ask the water company about a lead communication pipe. A round number from the internet is not a quote.
Sources
Key facts
- Before 1970
- DWI: lead pipework was commonly used to connect properties to the mains before 1970. That use was then banned. Older homes that have not been modernised may still have lead underground or indoors.
- After 1970
- DWI: a home built after 1970 is unlikely to have lead pipes. One built before 1970 may.
- Public supply
- DWI: lead is not present in the water in the wider public supply network. It can dissolve from lead pipework while water stands in the pipe. Natural lead in groundwater is described as rare in the UK.
- Test
- If you suspect lead, DWI says you can ask your water company to test the water at the kitchen tap.
- Standard
- The legal standard DWI publishes for lead is 10 micrograms per litre at consumers’ taps. This page does not state a pipe-replacement cost.
- What a survey sees
- Visible pipes only. The buried communication pipe, from the main to the outside stop valve, is the water company’s, and the surveyor does not excavate it.