Why Do You Need a Party Wall Agreement for Basement Conversion?

Why is it essential to have a party wall agreement for basement projects?

Well, when you dig a hole near another house and even under your own it's crucial to ensure proper design and execution. All you wouldn't want is someone's living room accidentally falling into the excavation! The underpinning of existing walls must be meticulously executed.

We've noticed that every basement project in London has resulted in some degree of damage ( minor) occurring even when the projects were well-designed, effectively managed, and properly constructed. The nature of work is invasive and building issues are bound to arise. This extract from BBC Inside Out demonstrates the type of damage that can occur.

What do we suggest? 

Before you start any basement construction work it's important to engage in discussions with your neighbors regarding the party wall. We can also guide you if your neighbor plans to carry out a basement excavation.

This is because if there is no connection between your property and your neighbors the Party Wall etc. Act 1996 mandates that you serve an Adjacent Excavation Notice under section 6 of the Act when you dig within 3 meters of your neighbor's property and go deeper, than their foundations.

Considering the complexity involved in constructing basements we highly recommend involving a Party Wall Surveyor at the initial stage to gather information and communicate effectively with your neighbors.

Do I need a Party Wall Surveyor?

If your basement is not in a detached property and if any excavations are within three meters of another property you will require a Party Wall Agreement. In this case, it is important to hire a party wall surveyor, with expertise and experience in dealing with basements.

To proceed with the Basement project it is crucial to gather all the right information;

1. Ensure you have all the basement calculations and engineering drawings for the works. In some cases, these can be prepared while dealing with Party Wall matters.

2. Obtain drawings to have an understanding of the project.

3. The significant document you'll need is the works information, which outlines how the basement excavation will be carried out. This is crucial because neighboring properties are at risk during this phase concerning potential extensions involving Party Walls.

4. Verify soil conditions by examining borehole and trial hole data.

5. It's important to secure funds for any expenses that may arise due to damages caused by the works on neighboring properties. This can be done by setting aside money in an escrow account, which will cover any work if required.

6. This situation often arises when undertaking high-risk projects particularly when neighboring properties have already undergone their construction work like loft conversions involving Party Walls. We suggest engaging a Surveyor to protect your interests and calculate funds, for the escrow account is essential.

If any damages are discovered after the completion of the works the Party Wall Surveyor will examine them and come to an agreed-upon financial arrangement. This agreement serves as a binding document, for all parties involved.