Party Wall & Boundary Disputes in Blocks of Flats
A comprehensive guide to party wall block of flats issues, covering the Party Wall etc Act 1996, when party wall notices are required, boundary disputes flats in leasehold properties, the role of structural walls leasehold buildings, and how to appoint a surveyor. Understand your rights and obligations when carrying out work to an internal party wall or resolving a dispute with a neighbouring flat.
What Is a Party Wall in a Block of Flats?
A party wall block of flats refers to any wall, floor, or ceiling structure that is shared between two or more separately owned or leased properties within the same building. In a typical block, this includes the vertical walls between adjacent flats on the same floor and the horizontal structures that separate flats on different levels. These shared structures are central to the physical integrity of the building and are subject to specific legal protections under the Party Wall etc Act 1996.
In leasehold blocks, the position is more nuanced than in a simple semi-detached house. The lease will typically define the extent of the demised premises, specifying which parts of the structure belong to the leaseholder and which are retained by the freeholder. In most cases, the structural walls leasehold properties rely upon are retained by the freeholder, meaning that leaseholders do not own the party walls themselves but are responsible for not causing damage to them. Understanding where your demise ends and the communal or structural elements begin is the first step in navigating any internal party wall issue.
For buildings that have been divided into flats from a single dwelling, party wall questions are especially common. Our converted flats management guide explains the particular challenges that arise in these properties, where the original construction may not have been designed with multiple occupiers in mind and the boundaries between flats can be less clearly defined.
The Party Wall etc Act 1996: Key Provisions
The Party Wall etc Act 1996 is the primary legislation governing party wall matters in England and Wales. It provides a framework for preventing and resolving disputes between neighbours when one party wishes to carry out building work that affects a shared wall, boundary, or structure. The Act applies to blocks of flats in the same way it applies to houses, though its interaction with leasehold law creates additional considerations.
Section 1: New Walls on the Boundary
Section 1 of the Party Wall etc Act 1996 deals with the construction of new walls on or astride the boundary between two properties. While this section is more commonly relevant to houses and gardens, it can apply in blocks of flats where new partitions are being erected in communal areas or where extensions are proposed that affect the boundary with an adjoining property. The building owner must serve notice on the adjoining owner before commencing any such work, and the adjoining owner has the right to consent or to have the matter determined by party wall surveyors.
Section 2: Work to Existing Party Structures
Section 2 is the provision most relevant to blocks of flats. It covers work to existing party walls, party fence walls, and party structures. This includes cutting into a party wall to insert a beam or damp-proof course, raising or reducing the height of a party wall, demolishing and rebuilding a party wall, and underpinning a party structure. In a block of flats, Section 2 is engaged whenever a leaseholder proposes work that involves cutting into, removing, or altering the wall or floor structure shared with an adjoining flat. This is the section that most commonly triggers the need for a party wall notice in residential blocks.
Section 6: Adjacent Excavation
Section 6 applies where a building owner proposes to excavate within specified distances of an adjoining property's foundations. In a block of flats, this can arise during basement conversions, underpinning works, or the installation of new drainage. The relevant distances are three metres for excavations to a depth below the adjoining owner's foundations, and six metres where the excavation intersects a 45-degree line drawn from the bottom of the adjoining owner's foundations. Where Section 6 is engaged, the building owner must serve notice and provide detailed plans and sections showing the proposed excavation and its relationship to the adjoining structure.
When Party Wall Notices Are Required
Understanding when a party wall notice is required is critical for any leaseholder planning works in a block of flats. The Party Wall etc Act 1996 requires the building owner to serve written notice on every adjoining owner who may be affected by the proposed works. In a block, this can mean serving notices on multiple neighbours, the freeholder, and in some cases the managing agent on behalf of the communal parts of the building.
Works That Require a Notice
A party wall notice must be served before carrying out any of the following works in a block of flats: removing or altering an internal party wall between two flats, cutting into a shared floor or ceiling structure to install steelwork or new services, underpinning or strengthening a party structure, excavating near the foundations of an adjoining flat, or constructing a new wall on the line of junction between two properties. Even works that may seem minor, such as chasing cables into a party wall or removing plaster from a shared wall to investigate damp, can trigger the requirement for a notice if they involve cutting into the party structure.
Notice Periods and Content
The notice must be served at least two months before the proposed start date for work under Section 2 (work to a party structure) and at least one month before work under Section 6 (adjacent excavation). The notice must describe the proposed work in sufficient detail for the adjoining owner to understand what is planned. For Section 6 works, the notice must be accompanied by plans and sections showing the proposed excavation. The adjoining owner has fourteen days to respond, after which a dispute is deemed to have arisen if no consent is given.
Consequences of Not Serving a Notice
Carrying out party wall works without serving the required notice is a breach of the Party Wall etc Act 1996. The adjoining owner can seek an injunction through the county court to stop the works, and may claim damages for any loss or damage caused. In a block of flats, proceeding without a notice can also put the leaseholder in breach of their lease, particularly where the lease requires compliance with all statutory obligations. The managing agent or freeholder may take action under the lease terms, and the cost of remedial works to repair any damage caused to the party structure can be substantial. For guidance on maintaining the structural elements of your block, see our building maintenance page.
Resolving Party Wall Disputes
Boundary disputes flats and party wall disagreements are among the most common sources of conflict between leaseholders in blocks. The Party Wall etc Act 1996 provides a structured dispute resolution process that avoids the need for court proceedings in most cases. Understanding how this process works is essential for both building owners and adjoining owners.
The Surveyor Appointment Process
When a dispute is deemed to have arisen under the Act, either because the adjoining owner has served a counter-notice or has failed to respond within fourteen days, the matter is referred to party wall surveyors. Each party may appoint their own surveyor, or the parties may agree to appoint a single agreed surveyor to act impartially for both. The surveyors must be independent and qualified to act in this capacity. Where each party appoints their own surveyor, the two appointed surveyors must select a third surveyor who can resolve any disagreements between them. This three-surveyor structure ensures that disputes can be resolved even where the appointed surveyors cannot reach agreement.
The Party Wall Award
The surveyors resolve the dispute by issuing a party wall award. This is a legally binding document that sets out the rights and obligations of both parties in relation to the proposed works. The award will typically include a description of the permitted works, the method of construction, the working hours and access arrangements, a schedule of condition recording the state of the adjoining property before works commence, and provisions for compensation if damage occurs. The award must be served on both parties and can be enforced through the county court. Either party has the right to appeal a party wall award to the county court within fourteen days of receiving it.
Disputes Beyond the Act
Not all disputes between neighbours in a block of flats fall within the scope of the Party Wall etc Act 1996. Disagreements about noise transmission through party walls, the responsibility for maintenance of shared structures, and the interpretation of lease boundaries may require resolution through the leasehold dispute process or through an application to the First-tier Tribunal. Where a dispute involves both party wall matters and broader leasehold issues, it is important to take advice on the correct forum for resolving each element of the disagreement.
Structural Walls vs Demise Boundaries in Leasehold Properties
One of the most important concepts for leaseholders in a block of flats to understand is the distinction between structural walls leasehold properties depend upon and the demise boundaries defined in the lease. This distinction determines who is responsible for maintaining, repairing, and insuring the wall, and whether the leaseholder has any right to carry out works to it.
Structural Walls and Freeholder Responsibility
Structural walls in a block of flats are the load-bearing elements that support the building. These include the external walls, the main internal walls that carry the weight of the floors and roof, and any walls that form part of the building's structural frame. In virtually all leasehold arrangements, these structural walls are retained by the freeholder and are not included within the demised premises of any individual flat. The freeholder is responsible for their maintenance and repair, and the cost of this maintenance is recovered through the service charge. Leaseholders do not have the right to alter structural walls without the freeholder's express consent, and any such alteration will also engage the Party Wall etc Act 1996. For more on how communal repair responsibilities are managed, see our communal repairs guide.
The Demise and Internal Partitions
The demise is the extent of the property that has been granted to the leaseholder under the terms of the lease. Typically, the demise includes the internal surfaces of the walls, floors, and ceilings within the flat, the non-structural internal partitions, and the fixtures and fittings. The lease plan will usually show the boundaries of the demise, though in older leases these plans can be imprecise. Internal non-structural partition walls that fall within the demise are the leaseholder's responsibility, and the leaseholder is generally free to alter or remove them subject to any lease restrictions on alterations. However, where an internal party wall is shared with a neighbouring flat, it may be partly within each leaseholder's demise, and the Party Wall etc Act 1996 may apply to any proposed works.
Common Boundary Confusion
Boundary disputes flats often arise from ambiguity in the lease about exactly where one flat ends and another begins. Common areas of confusion include whether the demise extends to the centre of a party wall or only to the plaster surface, who owns the space above a suspended ceiling or below a raised floor, and who is responsible for the window frames and external doors. These disputes are more common in converted properties where the original building was not designed as flats. Resolving these disputes requires careful analysis of the lease wording, the lease plan, and in some cases a surveyor's inspection to determine the physical construction of the boundary.
The Managing Agent's Role in Party Wall Matters
The managing agent plays a central role in overseeing party wall matters within a block of flats. While the managing agent is not a party to the Party Wall etc Act 1996 process itself, they are responsible for ensuring that the building's structural integrity is protected, that leaseholders comply with their lease obligations, and that disputes between residents are managed effectively. At Block, we take a proactive approach to party wall and boundary disputes flats issues.
- Reviewing and advising on leaseholder alteration requests that may engage the Party Wall etc Act 1996
- Ensuring leaseholders obtain the required freeholder consent before commencing any structural works
- Coordinating with party wall surveyors to protect the building structural integrity during works
- Maintaining records of party wall awards and schedules of condition for the building files
- Advising directors and freeholders on the implications of proposed works for the communal structure
- Mediating between leaseholders in boundary disputes and facilitating early resolution
- Instructing building surveyors to assess any damage to party structures caused by unauthorised works
- Liaising with contractors to ensure that communal repairs to structural walls are carried out to the required standard
Our experienced team understands the interaction between the Party Wall etc Act 1996 and leasehold law, and we work closely with leaseholders, freeholders, and appointed surveyors to ensure that party wall matters are handled correctly. Whether a leaseholder is proposing works that affect a party structure or a dispute has arisen about structural walls leasehold obligations, we provide clear guidance throughout the process. For more information about how we manage building maintenance and structural matters, contact our team.
Early involvement of the managing agent is particularly important where proposed works could affect the fire compartmentation of the building, compromise sound insulation between flats, or interfere with communal services that run through party structures. In these situations, the managing agent can coordinate between the leaseholder, the freeholder, and the appointed surveyors to ensure that the works are carried out safely and in compliance with both the Party Wall etc Act 1996 and the terms of the lease. Our communal repairs guide provides further detail on how we manage works to shared building elements.
Frequently Asked Questions About Party Walls in Blocks of Flats
What counts as a party wall in a block of flats?
In a block of flats, a party wall is any wall that separates two or more individually owned or leased properties. This includes the internal walls between adjacent flats on the same floor, as well as the floor and ceiling structures that divide flats on different levels. In leasehold blocks, the structural walls are almost always retained by the freeholder, while the internal non-structural partitions within each flat typically fall within the demised premises. Understanding what constitutes a party wall in your block is essential before carrying out any works, because the Party Wall etc Act 1996 imposes specific obligations on anyone proposing to carry out work to or adjacent to a party wall. If you are unsure whether a wall in your block qualifies as a party wall, you should consult the lease and seek advice from a party wall surveyor before proceeding with any building work.
Do I need a party wall agreement to renovate my flat?
Whether you need a party wall agreement depends on the nature and location of the work you intend to carry out. If your renovation involves work to a wall shared with a neighbouring flat, cutting into a party structure such as a floor or ceiling, or excavating near the foundations of an adjoining property, the Party Wall etc Act 1996 requires you to serve a formal party wall notice on the affected adjoining owner. Even relatively common flat renovations such as removing a non-load-bearing wall, installing new plumbing that passes through a party structure, or underpinning a floor can trigger party wall obligations. Failure to serve the required notice before commencing work is a legal breach and can result in an injunction, damages claims, and significant delays to your project. It is always advisable to seek professional advice before starting any renovation in a leasehold flat.
Who pays for a party wall surveyor in a block of flats?
Under the Party Wall etc Act 1996, the building owner who initiates the work is generally responsible for the reasonable costs of the party wall surveyor process. This includes the fees of their own surveyor, the adjoining owner appointed surveyor, and where applicable the fees of a third surveyor selected to resolve disputes between the two appointed surveyors. In a block of flats, this means that if you are a leaseholder proposing work that affects a party wall or party structure, you will typically bear the cost of the surveyor appointments. However, the position can be more nuanced where both parties are carrying out work simultaneously, or where the adjoining owner has made unreasonable demands that have inflated the costs. The surveyor fees vary depending on the complexity of the work and the number of adjoining owners affected, but leaseholders should budget for this cost as part of their renovation plans.
Can a freeholder prevent party wall works in a leasehold block?
A freeholder has significant control over works carried out within a leasehold block, and the position is more complex than in a freehold-to-freehold party wall situation. Most leases contain clauses that require the leaseholder to obtain the freeholder written consent before carrying out any alterations, particularly those affecting the structure of the building. Structural walls, external walls, and load-bearing elements are almost always retained by the freeholder and fall outside the demised premises. Even where the Party Wall etc Act 1996 permits certain works, the lease may impose additional restrictions or require specific conditions to be met. A freeholder can refuse consent if the proposed works would affect the structural integrity of the building, breach planning regulations, or conflict with the obligations owed to other leaseholders. Leaseholders should always check their lease terms and obtain freeholder consent before serving party wall notices.
What happens if my neighbour ignores a party wall notice?
If an adjoining owner does not respond to a party wall notice within fourteen days, the Party Wall etc Act 1996 deems that a dispute has arisen between the parties. Once a dispute is deemed to have arisen, the matter must be resolved by the appointment of party wall surveyors. The building owner and the adjoining owner may each appoint their own surveyor, or they may agree to appoint a single agreed surveyor to act for both parties. If the adjoining owner fails to appoint a surveyor within a further ten-day period after being requested to do so, the building owner surveyor may make the appointment on their behalf. The surveyors will then prepare a party wall award setting out the rights and obligations of both parties, including the permitted works, access arrangements, working hours, and any compensation payable. Ignoring a party wall notice does not prevent the works from proceeding; it simply triggers the statutory dispute resolution process.
How are boundary disputes between flats typically resolved?
Boundary disputes between flats in a leasehold block are typically resolved by reference to the lease plans and the lease demise clause, which together define the extent of each flat. Unlike freehold boundary disputes, which often rely on historic conveyances and physical features, leasehold boundary disputes are governed by the terms of the lease granted by the freeholder. Where the lease plans are unclear or ambiguous, the managing agent or freeholder may need to commission a surveyor to interpret the boundaries. If the dispute cannot be resolved informally, either party can apply to the First-tier Tribunal or the county court for a determination. Common boundary disputes in blocks include disagreements over shared hallways, storage areas, roof spaces, and the ownership of internal partition walls. Early involvement of the managing agent is often the most effective way to resolve these disputes before they escalate into costly legal proceedings.
Need Help With a Party Wall or Boundary Dispute?
Whether you are a leaseholder planning works that may affect a party wall block of flats, a freeholder dealing with an alteration request, or a director navigating a boundary disputes flats situation, Block is here to help. Our team has extensive experience managing structural walls leasehold buildings and coordinating Party Wall etc Act 1996 processes across residential blocks. We can guide you through the notice requirements, surveyor appointments, and dispute resolution procedures to protect both your property and the building as a whole. Explore our leasehold disputes guide for further information.