Buying a House With Unapproved Building Work

If you are buying or selling a property with an extension, loft conversion, outbuilding or other building works that were carried out without the correct planning permission or building regulations approval, the case of Cottingham v Attey Bower & Jones [2000] is an important case to understand.

The case is frequently referred to in conveyancing because it highlights the risks associated with unauthorised building works, missing building regulations approval, and the responsibility of a conveyancing solicitor to properly investigate alterations to a property.

Importantly, however, Cottingham v Attey Bower & Jones was not itself a planning enforcement case. It was a professional negligence case concerning the work carried out by conveyancing solicitors when buyers purchased a property where building works had been undertaken without the appropriate approval. (Today’s Conveyancer)

What was Cottingham v Attey Bower & Jones about?

The case involved Mr and Mrs Cottingham, who purchased a property where substantial renovation work had been carried out by the previous owner.

After the purchase, structural problems associated with the works became apparent. It was subsequently discovered that the previous owner had not obtained the necessary building regulations approval for the works and had not been completely forthcoming in the pre-contract enquiries.

The buyers brought a claim against their conveyancing solicitors.

The important issue was whether the solicitors had done enough to investigate the absence of building regulations approval and advise their clients about the potential consequences.

The court concluded that they had not.

The case is reported as Cottingham v Attey Bower & Jones [2000] Lloyd’s Rep. P.N. 591, decided in the Chancery Division on 30 March 2000. (Practical Law)

Why is Cottingham v Bower important?

The significance of Cottingham v Attey Bower & Jones is that it demonstrated that simply asking whether recent building work had the necessary approval may not always be enough.

At the time, the conveyancing guidance being followed included an approach that focused enquiries on relatively recent building works. However, the court considered the wider statutory enforcement powers available to a local authority.

Although certain enforcement powers under the Building Act 1984 were subject to a 12-month limitation period, the court considered the possibility of an application to the court for an injunction under section 36(6). That particular route was not subject to the same 12-month restriction. (Law Society Communities)

Consequently, the solicitors should have appreciated that an old building regulations problem could still present a risk to the purchaser.

This is one of the reasons the case continues to be cited in discussions about property conveyancing, missing building regulations certificates, unauthorised extensions and legal indemnity insurance.

Does Cottingham v Bower mean that a building without planning permission has to be demolished?

No.

This is an important distinction.

Cottingham does not establish a rule that a building constructed without planning permission must automatically be demolished.

Planning permission and building regulations are separate legal regimes.

A property can have:

• planning permission but no building regulations approval;

• building regulations approval but no planning permission;

• neither planning permission nor building regulations approval;

• or, in some circumstances, no planning permission because the work was permitted development.

Each situation needs to be considered separately.

Planning law is principally concerned with whether the development is lawful from a planning perspective, while building regulations concern matters such as structural safety, fire safety, drainage, ventilation, energy efficiency and other technical requirements.

What happens if a building was constructed without planning permission?

If development requiring planning permission was carried out without obtaining it, there may be a breach of planning control.

The local planning authority can potentially investigate the development and, where appropriate, take planning enforcement action.

The consequences can include an enforcement notice requiring steps to be taken to remedy the breach. Depending on the circumstances, that could potentially involve altering or removing unauthorised works.

However, the fact that a building was constructed without planning permission does not automatically mean that enforcement will be taken.

Planning enforcement is discretionary and depends upon the circumstances of the particular case.

There are also statutory time limits for planning enforcement.

The important planning enforcement time limits

The law changed significantly in England on 25 April 2024.

For certain types of development completed before that date, the previous four-year enforcement period continues to be relevant.

For operational development substantially completed on or after 25 April 2024, the enforcement period is generally 10 years.

Similarly, an unauthorised change of use of a building to a single dwellinghouse occurring on or after 25 April 2024 is generally subject to a 10-year period.

Other breaches of planning control already had a 10-year enforcement period. (GOV.UK)

The change was introduced by section 115 of the Levelling-up and Regeneration Act 2023, which amended section 171B of the Town and Country Planning Act 1990. (Legislation.gov.uk)

In simple terms

For England:

These rules have important exceptions and transitional provisions, so the age of a building alone should not be treated as conclusive evidence that it is lawful. (GOV.UK)

What does the four-year or ten-year rule actually mean?

A common misconception is:

“The building is more than four years old, so it automatically has planning permission.”

That is not quite correct.

The relevant concept is generally immunity from planning enforcement, rather than the original planning permission magically appearing.

For an older development, the owner may need to establish when the breach occurred and demonstrate the relevant facts with evidence.

Government guidance makes clear that it is not sufficient simply to state that a building is more than four or ten years old. Evidence may include dated photographs, invoices, receipts, witness statements and other documentary evidence. (GOV.UK)

Where appropriate, an owner may apply for a Lawful Development Certificate (LDC) to establish that existing development or use is lawful for planning purposes.

What about a building built without building regulations approval?

This is where Cottingham v Attey Bower & Jones becomes particularly relevant.

Planning permission and building regulations approval are two different things.

A building could therefore be immune from planning enforcement but still have an unresolved building regulations issue.

That distinction is extremely important when buying or selling a property.

For example, imagine that a homeowner built a two-storey extension 12 years ago.

The extension may now be immune from planning enforcement, depending upon the facts and applicable transitional rules.

But if there is no evidence that the extension complied with building regulations, there could still be concerns about its construction, safety and certification.

The lack of building regulations approval can therefore create problems even where planning enforcement is no longer available.

Can you sell a house without planning permission?

Potentially, yes.

There is no general rule saying that a property cannot be sold simply because historic works do not have planning paperwork.

However, missing planning documentation can create significant conveyancing problems.

A buyer’s solicitor may ask:

• When were the works carried out?

• What exactly was constructed?

• Was planning permission required?

• Was planning permission obtained?

• Was the work permitted development?

• Is there a Lawful Development Certificate?

• Was building regulations approval obtained?

• Is there a completion certificate?

• Has the local authority ever taken enforcement action?

• Is there evidence proving how long the building or use has existed?

• Is an indemnity insurance policy appropriate?

These enquiries can become particularly important where the buyer is obtaining a mortgage.

What is a lawful development certificate?

A Lawful Development Certificate, often abbreviated to LDC, is a planning document that can establish that existing development or use is lawful for planning purposes.

For an old unauthorised extension, for example, the owner may seek an LDC where the legal requirements for establishing immunity from enforcement are satisfied.

The certificate does not necessarily confirm that the building complies with building regulations.

That is another important distinction.

An LDC is therefore not a substitute for a building regulations completion certificate.

What does Cottingham mean for buyers?

The biggest lesson for a buyer is simple:

Do not assume that an old extension is automatically safe simply because it has been standing for many years.

A buyer should establish what approvals were required and whether appropriate documentation exists.

This is particularly important for:

• house extensions;

• loft conversions;

• garage conversions;

• basement conversions;

• new outbuildings;

• conservatories;

• structural alterations;

• changes of use;

• additional dwellings;

• barn conversions; and

• commercial property alterations.

The solicitor’s job is not necessarily to act as a building surveyor. However, where the conveyancing information raises concerns about alterations or missing approvals, further enquiries may be necessary.

That principle is one of the important lessons arising from Cottingham v Attey Bower & Jones. (Today’s Conveyancer)

What does Cottingham mean for sellers?

For sellers, missing planning permission or building regulations paperwork can cause a transaction to become delayed or potentially fall through.

If you know that an extension or other alteration was carried out without the appropriate consent, it is sensible to raise the issue with your conveyancing solicitor at an early stage.

Depending on the circumstances, possible solutions can include:

1. Retrospective planning permission

An application can sometimes be made for planning permission after development has already taken place.

2. Lawful Development Certificate

Where the statutory requirements are satisfied, an LDC may be available to establish that existing development or use is lawful.

3. Building regulations regularisation

Where building work was carried out without the necessary building regulations approval, a regularisation certificate may sometimes be available, subject to the relevant requirements.

4. Legal indemnity insurance

In some transactions, a lack of planning permission indemnity policy or lack of building regulations approval indemnity policy may be considered.

The appropriate solution depends heavily on the circumstances.

A major warning about indemnity insurance

Legal indemnity insurance is sometimes used during conveyancing where planning permission or building regulations paperwork is missing.

However, it should not automatically be treated as a solution to every unauthorised building works problem.

A policy can have exclusions and conditions, and the availability of cover depends upon the circumstances.

In particular, making contact with the local planning authority or otherwise drawing attention to a potential breach can affect the availability of certain types of planning indemnity insurance.

The issue should therefore be discussed with the conveyancer before contacting the council, where insurance is being considered.

Does Cottingham affect buildings built without planning permission today?

Yes, but indirectly.

Cottingham remains important because it demonstrates the importance of properly investigating missing approval and advising property purchasers about the risks.

It does not change the planning enforcement rules itself.

The current planning enforcement position in England is governed principally by the Town and Country Planning Act 1990, as amended, including the changes introduced in 2024.

The modern position is therefore a combination of:

1. planning law — was planning permission required?

2. planning enforcement law — can the council still take enforcement action?

3. lawful development certification — can the existing development be certified as lawful?

4. building regulations — was the construction compliant?

5. conveyancing law and professional duties — were the buyer and lender properly advised?

6. property value and mortgageability — will the missing approvals affect the transaction?

Cottingham is particularly relevant to the fifth point.

Why this matters when buying an older property

Suppose you are buying a property advertised as having a “large rear extension.”

The extension looks perfectly normal and appears to have been there for 15 years.

The estate agent says:

“It’s been there for years, so there shouldn’t be a problem.”

That statement alone is not enough.

You need to establish:

When was it built?

Was planning permission required?

Was planning permission obtained?

Was it permitted development?

Does the property have a Lawful Development Certificate?

Was building regulations approval obtained?

Is there a completion certificate?

Can the age of the extension be demonstrated?

Has the local authority ever taken enforcement action?

This is precisely why unauthorised building works can become a major issue during conveyancing.

Cottingham v Bower: the key takeaway

The case of Cottingham v Attey Bower & Jones [2000] should not be interpreted as meaning that every building constructed without planning permission is automatically unlawful forever, or that every unauthorised building must be demolished.

Instead, it is an important warning about the risks created by missing planning and building regulations documentation and the need for appropriate investigation during a property purchase.

For an existing building, the crucial question is not simply:

“Does it have planning permission?”

The proper questions are:

Was planning permission required?

If it was required, was it obtained?

If it was not obtained, is the development now immune from planning enforcement?

Can that lawfulness be demonstrated?

Was building regulations approval required and obtained?

What evidence and certificates exist?

Will the issue affect the property’s sale or mortgage?

That distinction can make a significant difference when dealing with an extension without planning permission, an unauthorised building, a house built without planning permission, or building regulations approval missing from a property.

Final thoughts

Cottingham v Attey Bower & Jones remains an important case for anyone dealing with property conveyancing, unauthorised building works, extensions without planning permission, missing building regulations approval and lawful development certificates.

The key point is that planning permission and building regulations are not the same thing, and the age of an unauthorised building does not, by itself, answer every legal question.

For older properties, establishing the planning history, obtaining the correct certificates and retaining evidence of when works were carried out can make a substantial difference when the property is eventually sold.

Important: This article is intended as general information about England and Wales and is not legal advice. Planning enforcement and building regulations cases are highly fact-specific. Anyone dealing with a particular unauthorised building should obtain advice from a suitably qualified planning professional or property solicitor before taking action.