Do I need permission to alter my leasehold flat?

Linz Darlington | August 2023

Many people make alterations to a leasehold flat without permission, and then own it for years or even decades without an issue arising. Equally, your solicitor might not have picked up on changes made by a previous owner, but this doesn’t mean the changes can’t cause you hassle in the future.

It is quite common that an issue only arises when the owner attempts to sell the flat or extend the lease, or the person from whom the permission should have been granted finds out about the change.

If you wish to make an alteration to your flat, we encourage you to ensure that the correct permission has been granted and properly documented.

When you make physical changes to your flat you might need three different types of permission. The first type applies just to leasehold properties, but the second two are relevant for most other residential property too.

Freeholder’s Consent – you may have to ask your freeholder’s permission to alter your property.

Planning Permission – if you wish to change the appearance of your property you may need planning permission.

Building Control Consent – if you are completing building works, you may need a certificate to provide it is safe

It is worth noting that the three types of permission above are not exhaustive. For example, if you own a listed building or the changes affect a party wall, you might need further consent.

The below article is not professional advice but may help you decide whether you need each type of permission or if you need to seek further advice.

If the changes have already been made and but you haven’t got the permission, it will point you in the direction of how to make it right.

If you want to make changes to your flat – either removing or adding things – then you may need to seek your freeholder’s consent for the changes.

When do I need to seek permission?

This really depends on what it says in your lease, and they vary.

You need to find the clause within your lease relating to alterations and consider exactly what it says. If there is no clause (which is very unlikely) then you are free to make alterations as you wish (but only to the property you actually own – see below!).

Common wording is often something like this “not to carry out any structural alterations or additions without the landlord’s consent.”

In the case above, this would certainly include major changes such as adding an extension or excavating a basement to create another room.

On the other end of the scale, some lease plans are sufficiently detailed that they show things like the location of kitchen appliances or the direction that a door opens. It is unlikely your freeholder would argue moving your sink would constitute a structural change.

There are lots of grey areas. For example, adding a plasterboard wall probably wouldn’t be considered a structural change. However, if you were to remove a wall then you should consider seeking permission – there could be a dispute in the future over the extent to which the wall was structural or not.

If the wording in your lease is ambiguous about whether you need to seek permission for a change, you should seek legal advice. This advice should ideally be in writing and retained in your records.

Can the freeholder say no to the changes, or charge for saying yes?

Again, this depends on what is written in your lease.

Fully Qualified Covenant: If your lease has a clause which says “…without the landlord’s written consent which cannot be unreasonably withheld” then this is called a fully qualified covenant. Your freeholder cannot say no unless there is a good reason – and there is plenty of case law setting out what “unreasonable” means.

Your freeholder can charge you for their professional fees to consider the change and give consent. They can also charge you for any reduction in value of your building or neighbouring properties they own caused by your alteration.

However, they cannot charge you a price simply to agree the change – because this would be considered “unreasonably withholding consent”.

Qualified Covenant: Even if the words “unreasonably withheld” are missing from the wording then it is usually considered implicit that consent can’t be unreasonably withheld.

The same rules as the fully qualified covenant apply.

Absolute Covenant: If your lease simply says you cannot make changes, then this is called an absolute covenant. It seems logical that just because the lease says that is it not possible to make changes, this wouldn't mean that the freeholder couldn't choose to authorise them if they wanted to - but this isn't necessarily the case. It was decided in a Supreme Court case called Duval that in certain cases the freeholder must refuse permission even if they would be happy to - for example if they have a similar restriction on other flats in the building and have an obligation to keep the covenants of each lease the same. If your freeholder is free to say yes, then they can charge you for the permission.

Have you checked you own the property you wish to alter?

It is quite common that leases of upper-floor flats do not explicitly include the loft space, even if they have sole access through a trap door. In these cases, it can be a grey area whether the loft space is owned by the leaseholder or retained by the freeholder. Another good example is the windows or external walls, which are often still owned by the freeholder even if you pay to have them maintained.

Before you start work, you should review the section of your lease which explains what you do and don’t own before you start work and if it isn’t clear, you may need to take legal advice. Your freeholder may wish to sell you this additional property, at a cost.

How do I seek permission?

The gold standard permission is a formal, signed document called a “Licence to Alter". This is a legal document which sets out the changes and often include before and after plans so it is completely clear on what permission has been agreed.

Whether you explicitly need a formal licence or not, we would encourage you to ask your freeholder for one. Whilst there will be a cost of getting this legal work done, it will mean that you know that there won’t be an issue in the future. Your solicitor should register this document – and any plans annexed to it – at the Land Registry. This means that it will be held electronically and available in the future.

If your lease doesn’t explicitly state that you need a “licence”, then you could just ask for written permission. This should always be on headed paper and signed by your freeholder. Or, if your freeholder is a company, a director of that company. It should confirm the changes in sufficient detail that there cannot be a dispute on what has or hasn’t been agreed.

Verbal or informal written consent (e.g., via email) is more likely to cause an issue in the future and is not recommended.

What happens if I didn’t get permission?

It is quite common for a freeholder’s valuer to inspect a property as part of a lease extension, and sometimes they pick up alterations made by the current owner or someone who owned the flat before them.

If they are unhappy with the changes, it is possible that your freeholder will insist the flat is put back to the way it was before. This is particularly likely if there is an absolute covenant preventing the changes or there is a good reason why they could reasonably prohibit it.

This isn’t always the case. We had a client who purchased the flat from someone who had removed a structural wall without the freeholder’s permission, but they had got building control consent (see below). Once provided with the building control certificate, the freeholder was happy the work had been completed properly and agreed to grant a lease extension so long as a new lease plan was included to show the changes.

In another case the freeholder wasn’t quite as relaxed. They required their own surveyor to inspect the work, and had their lawyer draw up a retrospective licence to alter to confirm the changes were agreed. This was an unexpected and unwelcome expense for our client.

Planning Permission

Planning permission deals with the appearance of proposed changes to your property, and the impact it will have on your neighbours or the environment around your flat.

When do I need to get planning permission?

To make some changes to your flat, you might need planning permission. These tend to be changes which affect the external appearance of the property rather than the internal configuration.

The rules for when permission is required are granular and the “permitted development” rules which apply to houses don’t always apply to flats.

For example, adding an extension to a ground floor flat is likely to attract planning permission.  In some cases you might need to get planning permission for a change of windows, if it changes the appearance or size.

How do I get planning permission?

You will need to apply via your local authority.

What if I didn’t get planning permission?

If you did not seek approval, you may need to submit a retrospective application – but this doesn’t mean it will be approved.

The local authority may ask you to make amendments to your flat, or even put it back the way it was.

In addition to planning permission, you must comply with the Building Regulations to show that the changes you are making are safe for the people living in and around them.

Many building activities fall under building regulations, but for work such as electrical work, plumbing and double-glazing the professional who completes the work should be registered as a “competent person”, and can self-certify their work. For example, if you have new double-glazed windows then the installer should give you a FENSA certificate to show that the work complies with the regulations.

Structural changes such as adding an extension or removing a structural wall will certainly attract building control regulations. Like-for-like replacement of your bathroom suite probably won’t. The Planning Portal website gives more information on when building control is required.

Unless your building work can be signed off by your tradesperson as a “competent person”, you or your tradesperson will need to apply to your local authority building control (LABC) service. Sometimes you can also use a private approved inspector.

You will need to speak to your local authority about what is required, and this is likely to depend on the type of work you are completing.

Once the work has been completed, you should receive a certificate which confirms is complies with local authority regulatory standards. You should keep this safe.

If you don’t get permission, you can usually contact your local authority and seek retrospective building control consent. This is known as ‘regularisation’.

It may be that, to sign off the work, building control need to inspect the property and prescribe corrective work to ensure compliance. This could be costly.

It may be that, to sign off the work, building control need to inspect the property and prescribe corrective work to ensure compliance. This could be costly.


It is important to do sufficient research before you make changes to your flat. If you are not clear you should seek advice from professionals.

If you have made changes to your flat and wish to rectify them, hopefully the above article will give you a basic starting point – although we would recommend seeking professional advice before you make your first move.

For example, it is worth noting that if you took out an indemnity insurance policy before you purchased your flat for changes made by a previous owner, this is unlikely to cover you if you “tip-off” the local authority about changes that have been made.

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Article author photo

Linz is the CEO and co-founder of Homehold. He’s always looking at how we can improve our service and better support you through the lease extension process. If you have any questions about your lease he’d be delighted to help.

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