Do I Need Planning Permission.co.uk
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I have discovered that the owner of the ground and second floor maisonette in the 4 storey house in which I live, has created a flat on the upper floor of her maisonnette.
The tenants accesses this new flat through the communal front door to the house, then through the entrance door to the maisonette and then through a new door which has been fitted within the maisonette separating off this new flat. A new kitchen has been created within this new flat and the tenants have use of the original bathroom of the maisonette.
I believe that the owner has created a shower room for herself on the ground floor. The ground floor does not have a separate entrance door within the maisonette.
The other 2 floors of the house are completely separate self-contained privately owned flats.
So officially there a 3 separate residences (A,B, and C) but there are now 4 separate dwellings?
Is this legal and safe?
The owner insists that she did not need any permissions as it only involved minor work, but something doesn't seem quite right to me.
I would be really grateful for any opinions and/or advice.
Thank you!

They would have required both Planning and Building Regulations. Both departments can take enforcement action should they be informed and the applicant isn’t forthcoming with any applications.