Well they did reply to me but to be honest I'm not convinced yet.
Olivia - no it's a 60s house so no issue there.
This is what the council planner said. (I googled him and on linked in he sounds like a trainee)
"Please see copied the passage from the General Permitted Development Order 2015 which are our guidelines on permitted development anything outside of this would need permission.
Conditions A.3 Development is permitted by Class A subject to the following conditions— (a) the materials used in any exterior work (other than materials used in the construction of a conservatory) must be of a similar appearance to those used in the construction of the exterior of the existing dwellinghouse;
As you described you would be changing the materials of your windows from white UPVC to grey aluminium therefore permission would be required."
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However...Class A refers to "Class A – enlargement, improvement or other alterat
ion of a dwellinghouse". We are replacing not any of the above.
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I've also just managed to find this on the planning portal website
"You do not usually need to apply for planning permission for:
repairs, maintenance, and minor improvements, such as repainting window and door frames
insertion of new windows and doors that are of a similar appearance to those used in the construction of the house"
The only reason I don't want to go down the planning permission way is that we have a REAL pain in the arse of a neighbour who is going to disrupt whatever we try to do.