Section 6 Party Wall Notices: Understanding Excavation Rules for Extensions and Basements

Excavation work is one of the most important stages of any construction project. Whether you're building a rear extension, converting a basement, or installing new foundations, your project could be subject to the requirements of the Party Wall Act.

Section 6 of the Act specifically addresses excavation and foundation work near adjoining properties. Understanding these requirements early can help prevent disputes, delays, and unexpected legal issues.

In this guide, we provide a detailed overview of the 3m & 6m Excavation Rules Explained and explain when a party wall surveyor may be required.

What Is Section 6 of the Party Wall Act?

Section 6 covers excavation and construction activities carried out close to neighbouring buildings.

The legislation exists because excavation work can directly affect the support provided to adjoining structures. If excavation is not properly managed, it may lead to movement, cracking, or structural damage.

To reduce these risks, the Act requires property owners to notify neighbours before certain excavation works commence.

The 3-Metre Rule Explained

The 3m rule applies when excavation takes place within 3 metres of a neighbouring building and extends below the depth of that building's foundations.

This provision is commonly triggered by:

• Single-storey extensions

• Double-storey extensions

• Garage foundations

• Outbuildings

Where applicable, a Section 6 Notice must usually be served at least one month before work begins.

The 6-Metre Rule Explained

The 6m rule is generally associated with deeper excavation projects.

Rather than focusing solely on distance, it uses a geometric assessment based on a 45-degree plane extending downward from the neighbour's foundation level.

If excavation enters this zone, notice requirements may apply.

Projects commonly affected include:

• Basement developments

• Piled foundations

• Large residential developments

• Structural redevelopment projects

What Information Must Be Included in a Notice?

A Notice of Adjacent Excavation and Construction typically includes:

• Details of proposed works

• Excavation depth

• Foundation design

• Construction drawings

• Planned start date

Providing clear information helps neighbours understand the scope and impact of the project.

What Happens After Notice Is Served?

The adjoining owner can:

Consent

The works can proceed without the need for a formal dispute process.

Dissent

A dispute is deemed to have arisen, requiring surveyors to prepare a Party Wall Award.

Request Further Information

Neighbours may seek clarification before responding.

Why Hire a Party Wall Surveyor?

A qualified party wall surveyor can manage the entire process, ensuring legal compliance and helping avoid disputes.

Their expertise includes:

• Technical assessments

• Notice preparation

• Surveyor appointments

• Schedule of Condition reports

• Party Wall Awards

Conclusion

Understanding Section 6 requirements is essential for any project involving foundation work near neighbouring properties. The Party Wall Act exists to protect both parties and ensure construction proceeds safely. Learning the 3m & 6m Excavation Rules Explained and engaging a professional party wall surveyor can help keep your project on track from start to finish.