Refurbishing Works to an Existing Shed

[allewitor]

We are currently refurbishing an existing tin shed building approximately 3m x 5m. We have introduced some new timbers and replaced the corrugated tin cladding. We have today received a letter from the local Planning Department stating "In respect of the hut that you are currently working upon, I can confirm that the works that you have carried our are currently unauthorised as no valid planning permission exists for such."

Can anyone please tell me if we are entitled to refurbish this existing shed and if any legislation exists that states we must apply for planning permission in order to do so. Could somebody direct me to a website which provides all of the relevant criteria. Thank you

[Poppy]

Well, it would seem the council doesn't currently think you are "entitled to refurbish this existing shed". I suggest that you contact them, find out what the issues are and comply with their requests.

Is the shed listed? Does it have special architectural significance? Any Romans buried beneath it?