What should you do if you are selling an extended home without planning permission?

Alterations to residential property often don't need planning permission. But what should you do if you have made alterations to your home that should have had planning permission and you want to sell you home?

Extended house

Typical home alterations

If you have lived in your home for a number of years, you may have made several improvements.

Perhaps you added a conservatory for extra living room, or a porch for everyone to leave their wet coats and dirty boots. You may have needed extra bedroom space and either added a two storey extension (to give you a bigger kitchen as well) or converted the loft into a master bedroom suite.

Most of these improvements could be classed as permitted development (PD) – a term given to works which may technically require planning permission but for which permission is deemed to be granted under a general permitted development order. This means that no application for permission has to be made or written consent obtained.

However, the rules surrounding permitted development are quite precise and you may find you have breached them if your home improvements have been extensive.


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What are the rules for permitted development?

The legislation set out in the Town and Country Planning (General Permitted Development) Order 1995 as amended by the Town and Country Planning (General Permitted Development) (Amendment) (No. 2) (England) Order 2008 details all the changes you can and can't make without planning permission.

With respect to extending your home, permitted development means you can add an extension to the side or rear of your house, providing its volume is less than 15% of the size of the original house. If your house is part of a terrace, the permitted size is less than 10% of the original volume.

However, if the extension takes up more than 50% of your garden, is higher than the original roof height or greater in volume than 115 cubic metres, planning permission must be applied for.

In addition, if your home had already been extended from its original size, say by 5%, you would need planning permission to add a further extension if the new extension was greater than 10% (or 5% if a terrace) of the property's original volume (i.e. a total of 15%/10% of the original house).

There are also rules about the permitted depth of extensions and their distance from the boundary of the property. Listed buildings or houses within conservation areas nearly always require planning permission to be granted before any alterations can be made. Some improvements, while classed as permitted development still need to have Building Regulations approval.

In general, it is responsibility of the person who carried out the work to make sure it complies with the regulations and issue a completion certificate.

What might happen to the 'saleability' of my home?

If your property appears to have been extended without the necessary planning consents or building regulations it may deter potential buyers since local authorities have the right to serve enforcement notices against property owners for breaches of the law – even if that person was not the owner at the time the work was carried out.

This might mean demolishing the structure, being fined or even imprisonment.

Action you can take before putting your house on the market

  • Make a list of any alterations you have made, detailing their dimensions and cross-referencing against the property's original size. This will demonstrate that the improvements can be classed as permitted development.
  • If you want to be certain that the existing use of a building is lawful for planning purposes or that your proposal does not require planning permission, you can apply for a 'Lawful Development Certificate' (LDC) from your local authority via the Planning Portal online application service. Although not compulsory an LDC may help you confirm that the use, operation or activity named in it is lawful for planning control purposes. There is fee of around £75.
  • Ensure that any completion certificates and Building Regulations approvals are available to show prospective buyers

"I think my extension may be in breach of planning regulations"

If your extension was completed more than 4 years ago and the local authority hasn't taken any enforcement action, it may have already lost its right to do so. Although this does not technically make the extension lawful, it does mean that no action can be taken against the new owner.

Retrospective planning permission

Where the extension exceeds permitted development, but has been completed within the last 4 years, it may be possible to make a retrospective application for planning permission. Depending on the work that has been done, the council should grant permission – provided it would have done so anyway before the work was carried out.

There will be a fee to pay and it may take a minimum of 8 weeks to process the application. However, there is a risk that permission may not be granted.

Indemnity insurance

An indemnity insurance policy can be taken out to provide cover against the risk of legal action being taken for a breach of planning regulations. Depending on the risk, the premium may be as little as £60 or as much as £500 – but is a once only payment, usually lasts the life of the property and automatically transfers to any subsequent owner of that property. A licensed conveyancer or solicitor will arrange the cover on your behalf.

You will need to confirm that the work was completed more than 12 months previously and that the house has been used as a residential dwelling for at least those 12 months.

It is important that there has been no contact with the local authority with regard to the property for at least the preceding 3 months. Although you will be expected to bear the costs, the application can be completed online and cover provided almost instantly.

Once cover is in place the policyholder may not contact the local authority about the property. To do so would invalidate the policy. Such a legal indemnity policy is acceptable to most mortgage lenders as claims can be made for the costs of complying with or defending any enforcement action brought by a local authority. It will also cover any resulting loss of value to the property – if the extension is ordered to be removed for instance.

Gaynor Haliday, Legal researcher

About the author

Gaynor Haliday is an experienced legal researcher and published author. She has had numerous articles published in the press and is a legal industry commentator.

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Questions: 2

Hi, I made an extension on my flat in 2013 without permission and I want to sell my flat what do I need to do. Several agents asked me if I have permission for the extension and I said No?. Please advice. Best kaisi

kaisi 25/09/18

Hi Kaisi,

The key thing here is to be honest from the beginning. The lack of planning consent will be discovered during the conveyancing process, so it would not benefit you to try to hide this.

If you are not in a hurry to sell, you could apply for retrospective consent. This would take a few months and you may not get retrospective permission. You could speak to a local architect or planning expert who should be able to tell you what your chances are.

Alternatively, you should speak to a conveyancing solicitor ASAP who will advise you on the extent of cover a suitable ?lack of planning? indemnity policy would provide. Once you know this, you can tell the agent you will be selling with an indemnity policy. You may wish to offer to pay for the policy. This approach should reduce the impact on the property?s value for being sold without planning permission.

Hope this helps

The Quittance Team, 09/10/18

Is it illeagal for a person to sell a property to a buyer when a the seller is aware that he has no planning permission for a block built workshop in the garden of the property?

Philip 02/10/18

Hi Phillip,

Although the seller may need to have applied for planning permission, selling a property without the correct planning approval in place is not illegal.

If the seller attempts to deceive you by not addressing this in the pre-contract enquiries and you, as a buyer, discovered this after completion, then you may have recourse.

Your conveyancing solicitor should be advising you on this. One course would be to insist that the seller applies for retrospective consent. However, this could be time-consuming and could scupper the sale.

It would be more common for an indemnity policy to be taken out on completion. It would be reasonable for the seller to pay for the policy, but this would be quick to arrange, and should not delay the sale.

The policy would indemnify against any reversionary costs if the Local Authority discovered the issue and insisted on the workshop being demolished. It would also cover you for any diminution of value in your property.

Hope this helps

The Quittance Team, 09/10/18