How will Party Wall Act 1996 affect your building project?

How will Party Wall Act 1996 affect your building project?

How will Party Wall Act 1996 affect your building project?

If you’re planning a building project in England or Wales that involves work on or near a shared wall, boundary, or neighbouring building, the Party Wall etc. Act 1996 is a critical legal consideration. The Act outlines procedures for notifying and coordinating with neighbours when construction works might affect their property—even in cases where no party wall exists.

At BB Partnership, we don’t act as party wall surveyors. We believe this is a specialist role involving significant technical and legal responsibilities. However, we have a strong understanding of how to design and manage projects that minimise risk, reduce disruption, and integrate Party Wall matters early into the build programme.

In this article we look at some aspects of the process, but this is not intended to be a definitive guide to the party wall act and our advice is always to contact an party wall surveyor.

What Is the Party Wall Act?

The Party Wall etc. Act 1996 applies in England and Wales and provides a legal framework for certain types of construction work that could affect neighbouring structures. It gives property owners the right to carry out essential works while ensuring that adjoining owners are protected through proper notification, inspection, and dispute-avoidance mechanisms.

What Is a Party Wall Award?

If a neighbour does not consent to your notice, or if formal oversight is preferred, one or more party wall surveyors are appointed to prepare an Award. This document outlines:

  • The scope and method of the works
  • Protective measures
  • Access arrangements
  • A schedule of condition of the adjoining property (crucial in assessing future claims)

Surveyors are appointed not to act on behalf of the individual owners, but on behalf of the wall—ensuring the work is carried out responsibly and that adjoining properties are protected. It is not a negotiation for neighbour “approval”; you already have the legal right to carry out the works. The Act exists to ensure they are done properly and safely.

When Does the Party Wall Act Apply?

You must serve notice under the Act if your project involves:

  • new building on or at the boundary of 2 properties
  • work to an existing party wall or party structure
  • excavation near to and below the foundation level of neighbouring buildings

This may include:

  • building a new wall on or at the boundary of 2 properties (the line of junction)
  • cutting into a party wall for any purpose (e.g. inserting a beam into a pocket).
  • raising, reducing, thickening or underpinning a party wall
  • removing chimney breasts from a party wall
  • demolishing and rebuilding a party wall
  • excavating below the foundation level of a neighbour’s property and within prescribed distances (e.g. to lay foundations, underpin a wall, construct a basement extension)
  • inserting a damp proof course into a party wall

Even seemingly minor works can fall within the scope of the Act. Failure to follow the process can result in project delays, legal action, or strained relationships with neighbours.

Our project in Stamford Hill for the demolition of an existing semi-detached house and rebuilding a new property that included a basement was complex in terms of the structural engineering solutions required, but the party wall process also includes relatively simple works as well that may only relate to the inside of a property including changes to the internal layout.

Excavation Works Near Neighbouring Properties

One of the most frequently misunderstood triggers for the Act is excavation. Even if there is no shared wall, notice must be served if you plan to excavate:

  • Within 3 metres of an adjoining structure and to a depth lower than its foundations
  • Within 6 metres, where the excavation would intersect a 45° downward line from the base of the neighbour’s foundations

This situation commonly arises with:

  • Basement construction
  • Foundations for rear or side extensions
  • Groundworks involving underpinning or retaining walls

To de-risk this process, we recommend working with your structural engineer early on to determine the likely depth of the neighbouring foundations and assess whether notices are required. But as a general rule of thumb foundations for new extensions or buildings will generally be deeper than those of an existing property as the depth of existing foundations will generally be shallower the older a building is.

Working With Flats: Multiple Parties May Need to Be Notified

If your property or the adjoining property is formed of flats, the situation is often more complex. In most cases, you will need to serve notice on both the leaseholder and the freeholder, and potentially obtain separate Party Wall Awards for each.

Note that tenants (renters) are not party to the process—only those with a legal interest in the property (freeholders or leaseholders) are involved.

What Is the Process?

Once it is confirmed that the Party Wall Act applies, the process typically unfolds as follows:

  • The building owner’s surveyor serves a formal notice to the adjoining owner
  • For party wall and excavation works, notice must be given at least two months in advance
  • For new boundary walls, one month’s notice is required
  • The adjoining owner then has 14 days to respond

While the Act does not require a qualified party wall surveyor to serve notices, at BB Partnership we strongly recommend that a party wall surveyor is involved from the outset. This ensures:

  • The design is reviewed with an understanding of Party Wall implications
  • Revisions to the scheme are considered before notices are issued
  • The correct type of notice is served, at the right time, in the proper format

Getting it right early helps prevent re-issuing notices, avoids invalid notices, and improves coordination with neighbours and their advisors.

What Happens After a Notice Is Served?

The adjoining owner may:

  1. Consent to the works — No further action is required.
  2. Dissent and appoint their own surveyor — A formal Party Wall Award is agreed between both surveyors.
  3. Dissent and agree to a single “agreed surveyor” — One surveyor acts impartially to draw up the Award.

If they do not respond within 14 days, dissent is assumed and a surveyor must be appointed on their behalf to draw up the award, although in this instance a detailed condition survey cannot be prepared.

Why Opt for a Party Wall Award?

While it is possible for neighbours to simply “agree” to the works, a formal Party Wall Award provides several advantages:

  • A schedule of condition which records the state of the neighbouring property prior to the works. This protects all parties and forms the basis of any future claims for damage
  • The works are carried out under agreed conditions, reducing uncertainty
  • Dispute resolution is handled through surveyors, not between neighbours
  • Legal protection is afforded to both parties

Although there is a financial cost, the benefits often outweigh the risks—particularly for more intrusive or structural work.

Special Foundations: What Are They and Why Do They Matter?

Under the Act, special foundations refer to reinforced concrete foundations (often including steel rods or mesh) that extend beneath the adjoining owner’s land. These are commonly used in basement construction and piled wall systems.

Crucially:

  • Special foundations require the adjoining owner’s written consent
  • Even with an Award in place, you cannot use special foundations under their land without approval
  • If refused, you may need to revise your design to use pad or mass concrete footings

Early consultation with your engineer and surveyor is essential if your design involves these foundations.

Can the Adjoining Owner Request a Structural Engineer Review?

Yes. Although not standard, adjoining owners may request that a separate structural engineer review the proposals—particularly if the works are complex or sensitive. This request is evaluated by the surveyors, and if deemed reasonable, the building owner typically bears the cost.

What are Security for Expenses?

A neighbour can request security for expenses, requiring the building owner to place funds in escrow to cover potential repairs or unfinished work. This is especially relevant for complex or high-risk works such as:

  • Basement excavations
  • Works in poorly maintained buildings
  • Large-scale structural changes

The amount is determined by the surveyor and held as a safeguard until the works are complete and inspected.

What Responsibilities does the Contractor Have?

While the legal process is managed through notices and surveyors, the contractor on site plays a key role in:

  • Adhering to the agreed methods set out in the Party Wall Award
  • Avoiding unnecessary disruption or encroachment
  • Cooperating with any access or protection measures required by the adjoining owner

Choosing an experienced contractor who understands the practical implications of the Award is critical to maintaining goodwill and compliance.

What Right of Access to Neighbouring Land do I have?

The Act provides the legal right to access a neighbour’s land (with notice) if it is necessary to carry out the approved works—e.g.:

  • Scaffolding erection
  • Excavation support
  • Finishing external walls

This must be managed sensitively, with clear notice and defined working hours. The right is not automatic for all situations, and misuse can result in legal challenge.

It is important to note that the access relates only to the party wall relevant matters and would not apply when building a new boundary wall that is not a party structure.

What If Work Starts Without an Award?

Carrying out notifiable works without an Award is a breach of the Act. Consequences include:

  • The adjoining owner can seek an injunction to stop work immediately
  • You may be held liable for any damage, regardless of fault
  • Legal costs and delays could escalate quickly

It is always advisable to resolve matters correctly before work starts.

What If the Design Changes on Site?

If the design or method of construction changes after the Award is agreed:

  • The surveyors may need to issue an amended Award
  • In some cases, a new notice may be required
  • Proceeding with changed works without updating the Award may invalidate your legal protections

This highlights the importance of finalising your design and sequencing before serving notices.

Do I Have to Pay to Use a Party Wall?

Yes. If you enclose onto or use an existing party wall, you may be required to compensate the adjoining owner. Typically, this involves:

  • Paying 50% of the cost of that part of the wall, based on current value and condition
  • The amount is agreed between surveyors and documented in the Award

Does the Award Cover Scaffolding or Access?

No. The Party Wall Act does not grant permission to oversail your neighbour’s property with scaffolding. For that, you’ll need:

  • A separate licence to oversail or access agreement, negotiated privately
  • These agreements are often handled by solicitors or agents, not party wall surveyors

However, the Act does provide limited rights of access to neighbouring land for construction, such as finishing a wall or installing waterproofing—provided it’s necessary and appropriate notice is given.

What Happens After the Works Are Complete?

At the end of the project:

  • The surveyor may conduct a post-works inspection
  • The current condition is compared with the original schedule of condition
  • If no damage is found, the matter is closed
  • If there is damage, the surveyor(s) decide on the remedy or compensation

Cost Considerations

Complying with the Party Wall Act may involve:

  • Party wall surveyor fees (usually the building owner pays for both)
  • Structural engineer reviews (if requested)
  • Design adjustments (e.g. if special foundations are refused)
  • Licences or agreements for scaffold oversail or access

While this does increase project costs, these expenses are minimal compared to the risk of legal claims, delays, or forced redesigns.


Our Role at BB Partnership

Although we do not act as party wall surveyors, we play an important role in helping our clients navigate the process effectively:

  • We identify works likely to trigger the Act early in design
  • Recommend experienced party wall surveyors suited to the project’s scale and complexity
  • Prepare clear drawings to support notices and Awards
  • Coordinate with structural engineers to avoid contentious solutions

Our aim is to streamline the process, reduce friction, and keep your project progressing with clarity and confidence.

Need Guidance?

Whether you’re planning an extension, a basement, or internal alterations to a flat, understanding your Party Wall obligations is essential. BB Partnership can help you anticipate and mitigate issues early—while working in collaboration with experienced party wall professionals.

Contact us today to discuss your project


Julian Williams

BA [Hons], Dip Arc, RIBA

Director

Susan Price

BA [Hons], Dip Arc, RIBA

Director

Manuela Barale

BA [Hons], Dip Arch, RIBA

Director