Party Wall Survey for Basement Works in London
Basement extensions and excavations are some of the most structurally demanding projects in London. They frequently involve deep foundations, underpinning or piling close to adjoining buildings — making compliance with the Party Wall etc. Act 1996 absolutely essential. At Hourican Associates, our Chartered Party Wall Surveyors in London specialise in Party Wall Surveys for basement works, helping homeowners, developers and adjoining owners navigate every step of the process.
Why Basement Works Fall Under the Party Wall Act
Most basement developments in London fall within the scope of the Party Wall etc. Act 1996 because excavation, underpinning and new foundations are carried out close to neighbouring structures. Before starting work, you’ll usually need to serve one or more of the following Party Wall Notices:
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Section 6 Notice – Adjacent Excavation Notice
Required when excavating within 3 metres (or in some cases 6 metres) of a neighbouring property and below the depth of its foundations. -
Section 2 Notice – Party Structure Notice
Applies if you intend to cut into, underpin, or otherwise alter a shared wall or structure. -
Section 1 Notice – Line of Junction Notice
Used if you’re constructing a new wall directly on or at the boundary line.
Our surveyors make sure all relevant Notices are correctly drafted, referenced to your structural drawings, and served on every adjoining owner, preventing delays or invalid notices that could halt your basement project.
The Role of the Party Wall Surveyor for Basement Works
Once Notices have been served, adjoining owners can either consent or dissent. If they dissent, each party must appoint a Party Wall Surveyor for the Building Owner and an Adjoining Owner’s Surveyor, or jointly appoint a single Agreed Surveyor, to prepare a legally binding Party Wall Award.
Our role as Party Wall Surveyors for basement projects typically includes:
- Reviewing structural and architectural drawings in detail.
- Assessing the potential impact of excavation, underpinning and piling on adjoining structures.
- Conducting a basement-focused Schedule of Condition Survey of neighbouring properties.
- Drafting and agreeing the Party Wall Award setting out how the basement works will proceed, including methods, sequencing and protection.
- Specifying protections, working hours, access rights and monitoring procedures.
- Inspecting works and advising on damage or movement if issues arise on site.
We act impartially to ensure both parties are protected under the law, while keeping your basement project moving safely and on schedule.
Why Basement Projects Require Extra Care
Basement excavations in areas like Chelsea, Kensington, Fulham, Chiswick and Westminster often take place in tightly packed streets with shared or historic foundations and complex underground services.
These projects demand precise engineering and proactive surveyor oversight to avoid:
- Structural movement or cracking in neighbouring buildings.
- Water ingress or damp problems caused by altered drainage or groundwater paths.
- Disputes over access, scaffolding, support works or vibration.
- Invalid, incomplete or late Party Wall Notices that delay construction.
Hourican Associates brings extensive experience in basement Party Wall Surveys and adjacent excavations, ensuring all documentation, inspections and agreements meet the highest professional and legal standards.
Typical Process for a Basement Party Wall Survey
Our process is designed to be robust but efficient, aligning the legal requirements of the Act with the practical needs of your project.
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Initial Consultation
We review your architectural and structural drawings, discuss your programme, and confirm which sections of the Party Wall etc. Act apply to your basement works. -
Serving Party Wall Notices
We draft and serve all necessary Party Wall Notices on relevant adjoining owners, ensuring they are valid, accurate and properly referenced. -
Surveyor Appointments
Either both parties appoint one Agreed Surveyor or each appoints their own surveyor. We can act in either capacity. -
Schedule of Condition Survey
We carry out a detailed Schedule of Condition Survey for basement works, recording the adjoining property’s condition before excavation begins. -
Preparation of the Party Wall Award
We prepare a comprehensive Party Wall Award setting out how the works will proceed, including methods of construction, protections, access arrangements, and damage resolution procedures. -
Ongoing Oversight
Where required, we provide site inspections, monitoring and further reports during and after construction, issuing supplemental Awards if needed.
For most basement projects, the Party Wall survey process typically takes around 3–5 weeks, depending on response times and project complexity.
Basement Party Wall Survey Costs
Our Party Wall Survey for Basement Works service typically ranges between £1,100 – £1,500 + VAT, depending on the size of the project, the number of adjoining owners and whether an Agreed Surveyor arrangement is used.
Where a Schedule of Condition Survey is required independently, prices for basement-related inspections normally start from £585 + VAT due to the detailed level of recording required.
Why Choose Hourican Associates
Hourican Associates is a specialist Chartered Building Consultancy with a strong track record in London basement projects. We’re trusted by homeowners, developers and architects for professional, thorough and legally robust Party Wall services.
- Chartered Building Consultancy regulated by RICS, CIOB and MCABE.
- Members of the Faculty of Party Wall Surveyors (FPWS) and Pyramus & Thisbe Society.
- Basement and structural work specialists with London-wide experience.
- Transparent pricing and clear communication from first enquiry to final Award.
- Impartial, fully compliant Party Wall services under the Party Wall etc. Act 1996.