Do I need planning permission to knock from my house to flat next door?

I live in a terraced house but it has a small kitchen and garden. I am thinking of buying the next door flat. It’s basically just the downstairs. 

Were I to ever manage this, would I need permission to knock my kitchen into theirs and add a door on the front under part of the house to connect them? 

Also I would like to combine the gardens so there is one big garden. GS

MailOnline property expert Myra Butterworth replies: Whenever the use of a property changes, then the issue of planning permission arises.

In this case, the building would change from two homes to one and so planning permission is will be required – and it may even be refused, so it is important to take advice.

Here, we speak to a planning expert for his thoughts on your unusual case.

Martin Gaine, a chartered town planner, replies: In a search for larger, better quality family homes, more and more people are buying two or more flats in a building and combining them into one property. 

Often, this improves the housing stock by getting rid of small, dingy flats in favour of larger family homes.

It is sometimes assumed that planning permission isn’t required because the changes are mostly internal, but it is a change of use – from several homes to one – and it is therefore likely that you will need consent.

It is also possible that your local council will object. The housing crisis is so severe in some areas that councils may focus more on the absolute number of housing units than on their quality. 

It is common for councils to have planning policies that say they will not grant permission for proposals that will result in a net reduction in the number of dwellings, and they strictly apply these policies.

The planning expert suggests that in this case, it is likely planning permission would be refused

Your case is unusual in that you have a terraced house and want to break into the ground floor flat next door. 

Although every case is different and you should take advice specific to your area, I’m afraid it is likely planning permission would be refused. 

Since you already have a full-sized house and the flat next door is probably a reasonable size, there is not the argument that you are removing undersized units to create a family home.

A house with a ground floor flat attached to it sounds like an awkward arrangement, and you may wish to remove the second front door – harming the street scene. 

The amalgamation of the rear gardens could also be said to affect the character of the area.

You should approach the local planners for advice – most offer a pre-application service – or speak to a planning consultant. 

If your proposal looks like a non-starter, consider alternative ways to enlarge your living space – most householders can build rear dormer loft extensions, ground and first floor rear extensions and large garden rooms using permitted development rights, i.e. without the need for planning permission. 

If that isn’t practical, sell up and move to a property already large enough to meet your needs.

· Martin Gaine is a chartered town planner and author of ‘How to Get Planning Permission – An Insider’s Secrets’