Party Wall Notices for Leasehold Flats: Who Needs to Be Notified?

Planning structural alterations to a leasehold flat in London can involve more people than you might expect.

You may own the lease to your flat, but the building could also have a separate freeholder, a management company and several other leaseholders. If the proposed work affects a shared wall, floor or another structure covered by the Party Wall etc. Act 1996, identifying the correct adjoining owners becomes an important part of the process.

A common mistake is to assume that notifying the person living next door is enough.

In a converted Victorian house or purpose-built block, the person occupying the neighbouring flat may not be its legal owner. The freeholder and a qualifying leaseholder may both have interests that need to be considered.

Party Wall notices for flats must be served on the relevant adjoining owners, which can include both freeholders and leaseholders. The correct recipients depend on the ownership arrangements, the structures affected and the proposed work.

This guide explains when the Act applies to flats, who needs to receive notice and why ownership checks should happen before construction begins.

Does the Party Wall Act Apply to Leasehold Flats?

Yes. The Party Wall etc. Act 1996 applies to qualifying work in England and Wales, including work involving flats.

It covers three main categories of construction:

• Work to an existing party wall or party structure.
• Construction of certain new walls at the boundary.
• Excavation within specified distances and depths of neighbouring buildings or structures.

Flats introduce an additional consideration because a shared structure is not necessarily a vertical wall between two houses.

A floor separating independently accessed flats can also be a party structure.

For example, a structural alteration to the floor between a ground-floor flat and a first-floor flat may engage the Act, depending on the nature of the proposed work.

However, not every refurbishment inside a flat requires a Party Wall notice.

Ordinary decoration, replacement of finishes and other work that does not involve a notifiable activity may fall outside the Act.

The correct starting point is to examine what is being altered, not simply whether the property is leasehold.

What Is a Party Structure in a Block of Flats?

The distinction between a party wall and a party structure is especially important for flats.

Under Section 20 of the Act, the definition of a party structure extends beyond shared walls. It can include a floor partition or another structure separating buildings or parts of buildings approached solely by separate staircases or entrances.

The GOV.UK Party Wall explanatory booklet specifically uses flats to explain this distinction.

Consider a Victorian townhouse converted into three flats.

The ground-floor and first-floor flats may be separated by a timber floor structure. The upper flats may also share load-bearing walls, roof elements or other structural components.

If the proposed work involves cutting into or altering a qualifying party structure under the rights provided by the Act, a Party Structure Notice may be required.

The building’s ownership and physical arrangement both matter.

A party structure should not be assumed to exist merely because two rooms are next to each other. The legal definition and the actual construction need to be considered.

Who Counts as an Adjoining Owner?

This is often the most complicated part of a Party Wall matter involving flats.

The Act uses a broader definition of owner than the person currently living in the property.

The statutory definition can include people or organisations holding freehold interests, qualifying leasehold interests, contractual purchase interests or rights to receive rent.

The government guidance explains that a leasehold title for a period exceeding one year can qualify.

Consequently, more than one person may be an adjoining owner in relation to the same property.

For a leasehold flat, relevant interests may include:

The freeholder

The freeholder owns the freehold interest in the building or relevant part of it.

Where that interest qualifies as an adjoining ownership interest affected by the proposed work, the freeholder may need to receive notice.

The adjoining leaseholder

A neighbouring flat owner holding a qualifying lease may also be an adjoining owner.

That person’s interest should not be overlooked simply because the freeholder has already been contacted.

Other qualifying owners

Depending on the building’s ownership arrangements, additional interests may need to be identified.

For example, ownership may be held through a company or there may be intermediate leasehold interests.

The legal and physical relationship between the properties determines who needs to be notified.

The key point is that notifying one person does not automatically satisfy the requirement to notify every relevant adjoining owner.

Do You Need to Notify Both the Freeholder and Leaseholder?

Potentially, yes.

If both hold qualifying adjoining ownership interests, each may need to receive a Party Wall notice.

This can happen where work affects the structure separating two leasehold flats within a building owned by a separate freeholder.

However, the answer should not be reduced to a universal rule that every freeholder and every leaseholder in the block must receive notice.

The relevant interests need to be assessed against the proposed work.

For example, a structural alteration affecting the party floor between two flats may require consideration of the leaseholder below and the relevant freehold interest.

That does not necessarily mean every flat on every floor must receive the same notice.

A Party Wall surveyor can review the proposed drawings and ownership information to establish which adjoining owners need to be included.

Does the Managing Agent Need a Party Wall Notice?

A managing agent is not automatically an adjoining owner merely because they manage the building.

Their role may involve collecting service charges, organising maintenance, communicating with residents or administering the building on behalf of the freeholder or management company.

Those responsibilities do not, by themselves, establish that the agent holds a qualifying ownership interest under the Act.

However, the managing agent can be an important contact.

They may help identify the freeholder, provide building information or explain the procedure for obtaining landlord approval for structural alterations.

A management company may also hold a relevant legal interest in its own right, depending on the ownership structure.

The distinction matters: the person managing a building and the person legally entitled to receive a Party Wall notice are not necessarily the same.

Does a Short-Term Tenant Need to Be Served?

A person occupying a flat under a short tenancy will not necessarily qualify as an adjoining owner under the Act.

A tenancy from year to year or for a lesser term is excluded from the relevant statutory definition of owner.

That does not mean the occupier should be ignored.

Construction may affect their living conditions, and the Act contains provisions concerning adjoining occupiers as well as owners.

Practical communication about access, working arrangements and disruption may therefore still be necessary.

The formal notice recipients should be identified according to the Act, while communication with affected residents should be managed appropriately.

What Work in a Flat May Require a Party Wall Notice?

The answer depends on the construction, but several common flat-renovation projects deserve particular attention.

Removing a load-bearing wall

An internal wall may appear to belong entirely to one flat while supporting floors, walls or roof construction elsewhere in the building.

Removing it can require structural engineering assessment.

Whether Party Wall notice is required depends on whether the proposed operation engages rights under the Act, such as cutting into or otherwise carrying out notifiable work to a party structure.

The fact that a wall is load-bearing does not, by itself, establish that it is a party wall.

Installing steel beams

Structural alterations sometimes require steel beams to be inserted into existing masonry.

Where the work involves cutting into a party wall to accommodate a beam, Section 2 may apply.

The engineer’s drawings should identify the structural supports, beam positions and proposed work to the shared structure.

AC Design Solution’s structural drawings and calculations can provide technical information relevant to this review.

Altering a shared floor structure

A proposed change to a floor between flats may involve joists, structural openings or new load-bearing elements.

The work needs to be assessed against the Act’s definition of a party structure and the particular rights being exercised.

Replacing a floor covering is not the same as structurally altering the floor.

Loft conversions in converted houses

A top-floor leaseholder may want to convert roof space into additional accommodation.

Such projects can involve steel beams supported by party walls, alterations to shared masonry or work affecting neighbouring structures.

There may also be separate questions about who owns the roof space and whether the lease permits the alteration.

A Party Wall notice cannot resolve those ownership and lease questions.

Basement works

Lower-ground-floor flats and basement developments can involve excavation close to neighbouring structures.

Section 6 may apply where the proposed excavation meets the statutory distance and depth tests.

For this type of work, the foundation information and excavation sections are particularly important.

Party Wall Notice Periods for Flats

The notice periods are determined by the type of work, not by whether the property is a flat or a house.

An earlier start may be possible where the necessary written agreement is obtained.

If an adjoining owner does not respond to a Party Structure Notice or qualifying excavation notice within 14 days, a dispute is generally deemed to have arisen, allowing the statutory surveyor process to proceed.

The response position for a new wall astride the boundary is different. Such a wall cannot be built astride the boundary without the adjoining owner’s written consent.

For further guidance on preparing and serving notices, see AC Design Solution’s Party Wall Notice service.

What If One Leaseholder Consents but the Freeholder Does Not?

Where multiple people qualify as adjoining owners, their responses must be considered individually.

One owner’s consent does not automatically amount to consent from every other relevant owner.

For example, a qualifying adjoining leaseholder may consent to the proposed structural work while the relevant freeholder dissents.

The statutory procedure may still need to be followed in relation to the dissenting owner.

A dispute can be resolved through an agreed surveyor appointed by both parties or through separate surveyor appointments, as appropriate.

The resulting Party Wall Award can determine relevant matters concerning the notifiable work, including its timing, manner and appropriate protective measures.

This is why serving notices on the correct parties at the beginning is important.

Discovering an overlooked adjoining owner after the project has been programmed can create avoidable complications.

Is Freeholder Consent the Same as a Party Wall Agreement?

No. These are separate matters.

A lease may require the flat owner to obtain a licence to alter or another form of landlord consent before carrying out structural works.

That requirement arises from the lease and the property’s ownership arrangements.

The Party Wall process is a separate statutory procedure dealing with qualifying work affecting adjoining owners and structures.

A freeholder granting permission under the lease does not automatically mean all necessary Party Wall notices have been served.

Equally, obtaining a Party Wall Award does not grant a leaseholder rights over parts of the building that they do not own or have permission to alter.

Planning permission and Building Regulations approval are also separate from the Party Wall procedure.

Before structural work begins, all relevant permissions and requirements should be checked.

How Do You Identify the Correct Owners?

The process usually begins with reviewing the available ownership information.

Land Registry records can help identify registered freehold and leasehold interests.

The lease documents may provide further information about the demised premises, retained parts of the building and ownership arrangements.

However, ownership information alone does not establish which parts of the structure will be affected.

The architectural and structural drawings must also be reviewed.

For a converted building, it can be useful to establish:

• Which flat or flats adjoin the proposed work.
• Whether a shared wall or floor is a party structure.
• Which freehold and leasehold interests relate to those areas.
• Whether structural works affect more than one neighbouring unit.
• Whether excavation could bring other properties within Section 6.

AC Design Solution’s Party Wall service includes reviewing property ownership and technical drawings before preparing the relevant notices.

Where ownership is disputed or unclear, specialist legal advice may also be necessary.

What Happens If an Owner Is Missed?

Failing to serve a required notice can leave the statutory procedure incomplete in relation to that adjoining owner.

The consequences depend on the circumstances and whether the relevant work has begun.

An omitted owner may object to the work or seek legal advice about available remedies.

The Party Wall Act does not provide a simple retrospective notice procedure that automatically cures a failure to follow the statutory process after the relevant work has started.

The appropriate response is to obtain advice promptly rather than assume that a later letter will resolve everything.

For a building with multiple ownership interests, checking the recipients before serving notices is considerably more straightforward than dealing with an omission during construction.

How AC Design Solution Approaches Party Wall Matters in Flats

Party Wall work involving flats requires both an understanding of the ownership arrangements and a clear picture of the proposed construction.

A notice template alone cannot establish whether a floor is being structurally altered, whether a steel beam will be supported in a party wall or whether the proposed excavation affects another building.

At AC Design Solution, Party Wall matters are led by Zubear Ali BA (Hons), ACIArb, MIPWS, MCMI, who has experience acting for building owners, adjoining owners and as an agreed surveyor.

The practice also provides architectural and structural engineering services, allowing the Party Wall review to be coordinated with the technical drawings where appropriate.

For flats, this means reviewing the work and identifying the relevant ownership interests before deciding which notices are needed.

The aim is not to notify as many people as possible. It is to identify the correct parties and follow the statutory procedure for the actual work being proposed.

Get the Correct Party Wall Advice Before Altering Your Flat

Leasehold flats require more careful Party Wall preparation because the building’s legal ownership and structural layout may not align neatly.

The adjoining flat owner, freeholder and other qualifying interests may all need consideration.

Identifying the correct recipients is just as important as identifying the work that requires notice.

AC Design Solution provides Party Wall surveying services across London, including notice preparation, ownership review, Schedules of Condition and Party Wall Awards.

If you are planning structural alterations to a leasehold flat, contact AC Design Solution with your property details and proposed drawings so the team can review the likely requirements.