Richard Hourican |
If you are planning a loft conversion, extension, basement or structural project close to a neighbouring property, you may have been told that you need Party Wall insurance.
The phrase can be confusing because there is no single statutory insurance policy created by the Party Wall etc. Act 1996. In construction and insurance discussions, “Party Wall insurance” is often used to describe additional cover for risks associated with works close to neighbouring buildings, particularly non-negligence insurance.
It should not be confused with a Party Wall Notice, Party Wall Award, Schedule of Condition or ordinary contractor public liability insurance. Each performs a different role.
This guide explains what Party Wall insurance usually means, when extra cover may be worth considering, what a Party Wall Award can and cannot do, and what London Building Owners and Adjoining Owners should check before higher-risk construction begins.
Quick Answer: Is Party Wall Insurance Legally Required?
There is no universal rule under the Party Wall etc. Act 1996 requiring every Building Owner to purchase a policy specifically called “Party Wall insurance”.
The Act instead creates a statutory procedure for notifying neighbours, resolving disputes and protecting adjoining property when certain works affect party structures, boundaries or neighbouring foundations.
Insurance requirements can arise separately through:
- the construction contract;
- the Building Owner's existing buildings insurer;
- the contractor's insurance arrangements;
- a lender or freeholder requirement;
- the project's particular construction risk;
- advice from an architect, surveyor, contract administrator or insurance broker.
That means the right question is usually not simply “Do I need Party Wall insurance?” but:
“What damage risks does this project create, which of those risks are already insured, and are there material gaps in cover?”
What Does “Party Wall Insurance” Usually Mean?
The term is used loosely in the market and can mean different things depending on who is using it.
In construction insurance, it commonly refers to non-negligence insurance. You may also hear terms such as:
- Party Wall liability insurance;
- non-negligence cover;
- JCT 6.5.1 insurance;
- 21.2.1 insurance, using older JCT terminology;
- insurance for damage to adjacent or surrounding property.
The important point is to read the actual policy wording rather than relying on the informal name.
A policy sold under the label “Party Wall insurance” should be checked for exactly which events, properties, construction activities, exclusions, excesses and indemnity limits it covers.
Public Liability Insurance and Non-Negligence Insurance Are Not the Same
A contractor's public liability insurance will usually deal with specified third-party injury or property-damage liabilities arising from the contractor's activities, subject to the policy wording.
However, construction next to existing buildings can create situations where damage occurs but proving contractor negligence is not straightforward.
Non-negligence insurance is designed for specified categories of damage where liability may arise even though the damage cannot readily be attributed to a negligent act by the contractor or subcontractor.
| Protection | Primary purpose | Important limitation |
|---|---|---|
| Contractor public liability insurance | Third-party injury or property-damage liability arising from insured contractor activities. | Policy triggers, negligence requirements, exclusions and limits vary. |
| Non-negligence / Party Wall liability insurance | Specified damage risks where negligence may not be established, particularly around neighbouring property. | It is specialist cover and is not automatically required for every Party Wall project. |
| Party Wall Award | Sets out how notifiable works may proceed and records appropriate safeguards and procedures. | An Award is not an insurance policy. |
| Schedule of Condition | Records the adjoining property's condition before works begin. | It provides evidence, not financial indemnity. |
| Security for expenses | A statutory financial safeguard that may be requested in appropriate Party Wall circumstances. | It is not the same thing as an insurance policy. |
When Might Non-Negligence Insurance Be Considered?
Additional cover tends to become more relevant as the potential consequence of movement or damage increases.
Examples can include projects involving:
- basement excavation;
- underpinning;
- deep excavations next to neighbouring foundations;
- piling;
- substantial demolition;
- temporary removal or weakening of structural support;
- significant vibration;
- groundwater changes;
- older or particularly sensitive adjoining buildings;
- high-value neighbouring property;
- commercial premises where interruption could create significant loss.
A straightforward domestic loft conversion is therefore a very different risk from a deep basement beside a fragile period townhouse.
If your scheme involves a basement, underpinning or significant excavation, our Party Wall basement works service can review the statutory and technical Party Wall implications.
For foundations and other works close to neighbouring buildings, see our Party Wall excavation survey service .
Does a Party Wall Award Provide Insurance?
No.
A Party Wall Award is the formal document produced by the appointed surveyor or surveyors where a dispute has arisen under the Act.
It can set out matters such as:
- the notifiable works that may proceed;
- approved drawings and structural information;
- working methods relevant to the Party Wall matter;
- protective measures;
- access arrangements;
- working times where relevant;
- inspection procedures;
- how Party Wall damage concerns should be addressed;
- reasonable costs within the surveyors' jurisdiction.
The Award creates a structured framework for the works. It does not replace appropriate construction insurance.
Learn more about the statutory document on our Party Wall Awards London page.
Why a Schedule of Condition Still Matters When You Have Insurance
Insurance cannot remove the need for good evidence.
If an Adjoining Owner reports cracking after excavation begins, one of the first practical questions is whether the cracking existed before the project.
A Schedule of Condition creates a written and photographic record of the adjoining property before works start.
That can help the parties, surveyors, contractors and insurers distinguish:
- pre-existing cracking;
- historic movement;
- existing damp or water staining;
- previously damaged finishes;
- genuinely new changes after construction begins.
The Schedule does not prevent damage and it does not provide financial cover. Its value is evidential.
What Is Security for Expenses?
Security for expenses is another Party Wall concept sometimes confused with insurance.
In appropriate circumstances, an Adjoining Owner may request financial security before works proceed under the Act. The purpose is to provide protection against the risk of a Building Owner beginning relevant works and then leaving the adjoining property exposed or the project incomplete at an inconvenient stage.
This can become particularly relevant on substantial excavation, underpinning or basement projects where unfinished structural work could have serious consequences.
Security for expenses is not an insurance policy. It is a separate statutory financial safeguard and should be considered on the facts of the individual project.
Can an Adjoining Owner Demand Any Insurance Policy They Want?
Not simply because they are worried about the works.
An Adjoining Owner has important rights under the Party Wall Act, including the right to receive the appropriate notice, appoint a surveyor where a dispute arises, seek reasonable safeguards and receive compensation or making good where relevant damage is caused.
However, Party Wall rights need to be distinguished from:
- requirements under the Building Owner's construction contract;
- requirements imposed by a lender;
- freeholder or lease requirements;
- general construction insurance requirements;
- separate private agreements between neighbours.
If you have received a notice and are concerned that the proposed insurance or protection arrangements are inadequate, our Adjoining Owner's Surveyor service can review the proposals in the context of the Party Wall process.
Building Owners: What Insurance Should You Check Before Work Starts?
The precise answer should come from your insurer, broker and professional team, but a sensible project review will usually consider several layers of cover.
Your existing buildings insurance
Tell your insurer about significant structural building works before construction starts. Do not assume your existing household or commercial buildings policy will remain unchanged while major excavation, structural alteration or renovation is underway.
The contractor's public liability insurance
Obtain current evidence of the contractor's insurance and check that the policy is appropriate to the nature and scale of the proposed works.
Contract works insurance
Establish who is insuring the new works, materials and relevant existing structure during the contract.
Non-negligence insurance
Ask your broker and project team whether the construction risk justifies additional cover for specified damage where negligence may not be established.
Professional indemnity insurance
Architects, structural engineers and other professional consultants should carry appropriate professional cover for their own services. This is different again from contractor or Party Wall-related construction insurance.
What Should You Send to Your Insurance Broker?
A broker cannot accurately assess a project from the phrase “house extension” alone.
Provide enough information to explain the genuine construction exposure, including:
- existing and proposed architectural drawings;
- structural drawings and calculations;
- foundation depths and types;
- excavation sections;
- details of underpinning or temporary works;
- distance to neighbouring structures;
- information on neighbouring basements where known;
- project value and anticipated programme;
- contractor details;
- the proposed construction contract;
- relevant Party Wall Notices;
- the Party Wall Award where one has been made;
- Schedules of Condition where available.
Material changes to the structural design should also be communicated during the project rather than assuming the original insurance assessment automatically covers every revised method.
Party Wall Insurance and Basement Projects
London basement projects deserve particular attention because the works can involve a combination of excavation, underpinning, temporary support, groundwater management and structural changes beside valuable neighbouring buildings.
The insurance question should therefore sit within a wider pre-construction risk process that includes:
- Party Wall notices;
- surveyors' appointments where required;
- detailed structural design;
- temporary works planning;
- a thorough Schedule of Condition;
- a robust Party Wall Award;
- contractor competence;
- appropriate project insurance;
- monitoring where technically justified.
No single document performs all of those functions.
Party Wall Insurance and Rear Extensions
Many London rear and side-return extensions involve new foundations close to the neighbour's house, extension, garden structure or basement.
Where Section 6 applies, the Building Owner may need to serve an excavation notice before those foundations are dug.
A modest domestic extension will not automatically require specialist non-negligence insurance simply because a Party Wall Notice is required. The insurance decision should reflect the actual design, depth, proximity, neighbouring structures and contract.
The statutory process should nevertheless start correctly through valid Party Wall Notices .
What If the Neighbour Consents to the Notice?
Written consent to a valid Party Wall Notice can mean that the formal surveyor and Award procedure is not required for that owner.
Consent does not make construction risk disappear.
The Building Owner should still consider:
- the contractor's insurance;
- their own buildings insurance;
- the construction contract;
- the suitability of the proposed method;
- a pre-works Schedule of Condition;
- whether specialist cover is justified by the project risk.
This is an important distinction: Party Wall consent deals with the statutory notice process. It is not an insurance waiver from the neighbour.
What Happens If Damage Occurs?
If damage is reported during or after notifiable works, do not start by arguing about insurance.
First establish the facts.
- Record the reported damage promptly.
- Compare it with the pre-works Schedule of Condition.
- Notify the appointed Party Wall Surveyor or surveyors where appropriate.
- Notify the contractor and relevant insurers in accordance with policy conditions.
- Obtain structural or specialist advice where the damage may be significant.
- Avoid carrying out irreversible repairs before appropriate inspection and evidence gathering.
An insurance claim and a Party Wall damage procedure may interact, but they are not the same process.
Where the matter becomes disputed, our Party Wall dispute resolution service can help determine what falls within the statutory process.
Party Wall Insurance Checklist for Building Owners
- Confirm which elements of the proposed works fall under the Party Wall Act.
- Serve all required Party Wall Notices before starting notifiable work.
- Tell your own buildings insurer about significant structural works.
- Obtain the contractor's current insurance certificates and policy information.
- Check insurance requirements in the construction contract.
- Ask whether non-negligence cover is appropriate for the project's risk profile.
- Provide the broker with proper drawings and excavation information.
- Arrange a Schedule of Condition where appropriate.
- Ensure the Party Wall Award reflects the agreed notifiable works and safeguards.
- Review insurance again if the design or method changes materially.
- Keep all notices, Awards, condition reports and insurance records together.
If you are carrying out the works, our Building Owner's Surveyor service can review the Party Wall aspects of the project alongside your drawings and construction programme.
The Key Principle: Insurance, Evidence and the Party Wall Process Work Together
Party Wall insurance is not a substitute for following the Party Wall etc. Act 1996.
Equally, a properly served notice or well-drafted Party Wall Award does not insure the construction project.
A well-managed project usually combines several layers of protection:
- a competent design team;
- a competent contractor;
- the correct Party Wall Notices;
- an appropriate Schedule of Condition;
- a Party Wall Award where required;
- sensible construction methods and monitoring;
- appropriate insurance arranged with specialist advice.
The more complex the excavation or structural work, the more important it is to review those protections as one coordinated risk strategy rather than as isolated pieces of paperwork.
Party Wall Insurance FAQs
Richard Hourican, Company Director
BSc (Hons). HND Build. MCIOB. C.Build E MCABE. ARICS. MFPWS. MPTS
As a specialist Party Wall surveyor, Richard Hourican will protect your interests during building works.
Are you planning a building project – perhaps an extension, loft conversion or basement – that is on or adjacent to your property’s boundary line? Or has a ‘Party Wall’ notice dropped on the doormat informing you of a neighbour’s impending works?
It’s essential to understand all the implications of building plans. If you don’t, it could cost thousands. Our job is to ensure everything is done correctly – and that it doesn’t!
Follow us:
