Owning your own home

If you can get a copy of the lease then this will tell you what the provisions of the lease are regarding alterations, whether or not you need the consent of the landlord or whether it's an absolute covenant against alterations. If it's a covenant against making alterations without consent then section 19(2) of the Landlord and Tenant Act 1927 means that the landlord cannot unreasonably withhold consent if the works are an 'improvement'. Whether or not they're an improvement is determined from the point of the tenant, so it almost always will be. However, it probably won't be possible to get a yes/no answer from the landlord before buying the property.

In terms of planning consent you should be able to have an informal chat with the local planning officer to get some idea of whether the extension would be allowed, or whether it would be a permitted development and so would not require consent, but again you're unlikely to be able to get formal planning consent before buying unless the conveyancing process takes an exceptionally long time.

Thanks, that's pretty much what I thought. Although I was under the impression that the air around the property often falls outside of the demise of the lease so section 19(2) doesn't stand? I'd presumably need a party wall agreement with the other tenant(s)?

Feels like it's pretty much impossible to find out with any degree of certainty whether it's feasible to extend prior to purchase.