If you’re planning building work near a neighbour’s property, you will need to be aware of the Party Wall Act 3 metre rule. Whether you are planning an extension, building the foundations for an outbuilding or creating a basement, there are legal steps you must take.

The 3 metre rule is part of the Party Wall Act 1996. It outlines the responsibilities of the person undertaking any building work on or near shared property boundaries. It’s not designed to prevent you from building; it’s there to protect neighbouring properties and to ensure everyone stays informed. 

What is the Party Wall Act? 

The Party Wall Act is a legal framework that exists to prevent and resolve disputes between neighbours during construction projects. There are three primary situations in which the Act is applicable. They are: 

• When working on a shared party wall 
• Building close to or on the boundary line 
• Excavating near a neighbour’s property, such as a house, garage or shed 

Even if your property is detached, the Act can still apply if you are digging near the boundary of your property. This is where the 3 metre rule comes into play. Read our case studies to see how a Party Wall Award can help protect property owners during construction projects.  

What is the 3 metre rule?

If you’re planning on excavating for building works, then the 3 metre rule must be adhered to. As part of the Party Wall Act, the 3 metre rule is triggered when you plan to dig: 

• Within 3 metres of a neighbouring structure 
• To a depth lower than your neighbour’s foundations

If both of the above scenarios apply, then by law, you’re required to serve your neighbour with a formal notice, known as a section 6 notice. This should be given to them at least one month before work commences. 

When might you encounter the 3 metre rule? 

Typical examples of when you may have to follow the 3 metre rule could be building a rear or side extension, adding a basement or installing deep drainage or new footings. For example, if you’re digging foundations 2.5 metres from your neighbour’s house and going 1.8 metres deep, while their house foundations are only one metre deep, you will need to serve a section 6 notice. 

What does a section 6 notice involve? 

While there is no official section 6 notice document or form for you to complete, there is some guidance on what the notice should include. You must give written notice to your neighbours at least one month before work begins and include: 

• The date notice is served, and when it expires 
• Your name and address 
• The address of the building to be worked on 
• A full and accurate description of what you propose to do 
• When you propose to start (which must not be before the relevant notice period has elapsed)
  

Why is the 3 metre rule important?

Failure to comply with this section of the Party Wall Act 1996 can result in delays to your building project. Your neighbour may even take legal action against you or force you to stop all work until the issue is resolved.

If you continue to excavate without issuing a section 6 notice, and the work you carry out causes damage to your neighbour’s property, then you could be liable for the repairs.

Do you need party wall and boundary dispute advice?  

If you’re looking for advice on party wall and boundary disputes, we can help you understand your rights and ensure you follow the right legal steps. Please contact a friendly member of our party wall services team to discuss your requirements.