Assess your risk to lead

When was your property built?

• Knowing when a property was built provides an indication of whether or not lead supply pipes may be present. 
• The use of lead pipes for domestic plumbing was stopped in 1974. Thus, if the property was built after 1974 there should be no lead pipes.
• For property owners the property age will be detailed in the property deeds. For tenants you may need to ask the property owner. 
• You may be able to get a guide to the age of the property by asking a near neighbour in a similar property.
• If you select don't know the programme will assume it is pre 1974.
• If you select the option that the property was built after 1974 then your lead risk is minimal already.

Length of Supply pipe for Properties with Separate Supplies

Estimate the length of pipe from the kitchen tap the internal stop tap for the property, , and the distance from the stop tap to the property boundary. If lead is present either side of the stop tap add  the two lengths. If lead is present only on entry to the property at the stop-tap, then take the distance of the stop tap to the property boundary as the relevant length scale to enter. Conversely, if lead is only present inside the property use the distance from the stop tap to the drinking water tap  If length of lead pipe is less than 3 metres then select well below average, if greater than 30 metres then select well above average. If between 3 and 30 meters select average.

Length of lead for Property with Common Supplies

For most cases, selection of the average property is appropriate. Select very long lengths if you estimate the total amount of lead supply pipe on your property exceeds 30 metres.

Do you have lead pipes?

If there is no lead pipe, then your lead risk is likely to be minimal. However, determining whether or not lead pipes are present may require some investigation.

It is important to note that in many properties a mix of materials may have been used for the supply pipes so it's worth checking the pipe material in at least two locations:

• under the kitchen sink,
• at the internal stop tap.

One major feature that helps identify the pipe material is its colour:

• Plastic - comes blue, white or black
• Copper  - copper colour, but dull when not polished, and corrosion products on the surface are green
• Lead pipes are usually dull grey/white patina.
• Galvanised pipe are also dull grey but occasional signs of rust.

Another feature is the curvature of the pipe. Lead in very malleable and a lead pipe will often have irregular bends which you would not expect from other materials.   Polymeric materials will only bend to a large radius, and the curve will be perfectly uniform.  Galvanised iron pipes are likely to be in straight lengths with separate bends.   Copper pipes can be formed into bends.)

A look under the kitchen sink may suggest that the supply pipe inside the property is plastic or copper. However, it is important to look in other places.

The only place where the pipe is nearly always visible is where it enters the house, often in the corner of the kitchen, between the floor and the stop-tap.  There also may be pipe visible e.g. in an outside toilet, but this will not necessarily represent the material of the incoming supply pipe - although it is a good clue.

A lead pipe is unlikely to have any visible external markings, and nor can it be identified by diameter, as this varies widely.  Because of its thick wall however, a half-inch lead pipe will appear much larger than a half inch copper or galvanised pipe. However the outside diameter will be roughly similar to a modern 25mm pipe.

A characteristic sign of lead is the 'wiped joint' (see picture), which is used to join lead with another material. Sometimes the lead will be attached directly to the body of the stop-tap, again with a wiped joint.  The pipe will appear enlarged as it meets the tail-piece, and will appear to merge with it i.e. there are no nuts, washers etc and the joint cannot be dismantled.  On the downstream side of the stop-tap there be a variety of joints depending on the material of the internal plumbing - another wiped joint if the plumbing is lead, or a mechanical coupling if it is copper.

Lead is a very soft metal so scratching the surface is easy and will leave shiny marks.

Tapping lead pipes with a coin will make a dull noise rather than the metallic ringing of a copper pipe.

Household paint adheres well to lead pipe.

Check with your neighbours.  It is almost certain that if their house was built at the same time that similar plumbing materials will have been used. They might know - if for example they have carried out any repairs or alterations.

Metallic pipes will usually have electrical earth wires attached to them. This will never be the case with plastic.

What type of supply pipe do you have?

• There are two types of supply pipe (see diagrams below). The majority of customers have a direct feed from the water mains in the street. This is called a separate supply pipe. However, about 10 % of customers share a supply pipe with a number of neighbours. This is called a common supply pipe.
• If you are a household customer, you (or your landlord) are responsible for the water supply pipe from the boundary of the property where our main is situated to your home. You are also responsible for any other water pipes within the boundary of your property and for the plumbing inside your home.
• Common supply pipes are the joint responsibility of all the homes that are served by the pipe. This may be you and your neighbours (and or their landlord(s)).
  The type of supply pipe you have influences your lead risk and determines what options are available to you.

How can you tell what type of supply pipe you have?

• If you have an external water meter then you have a separate supply.
• If the flow of water is influenced by a neighbour's water usage then this would indicate that you have a common supply.
• Ask a near neighbour - if you have a common supply then a neighbour may already have determined the supply type arrangement.