Garage planning permission

[Roxie85]

Hi.
I'm wondering if I can have some help.
We live in a semi detached house and have an attached garage which protrudes about 2m from the front of our house on the side that isn't attached to another house. We are going to be converting the garage into an office and downstairs toilet, putting a window at the front. We are aware that we need building regs for this but not planning permission.
However we are thinking of changing the roof from flat to pitched and are unsure if we need planning permission. I've called the council and they've not been very helpful, just directing me to forms that are for unattached garages.
I know a friend who is building a single storey extension which is covered by permitted development so don't see why changing a garage roof should need planning permission if that doesn't. The roof would only be from underneath the bedroom windows on the first floor to the top of the garage.
We've had to book the builder already as need it doing over summer so if we need planning permission we'll have to stick with a flat roof as there won't be time to get permission.

[clmustard]

The problem is that it protrudes to the front of your house so couldnt be treated as a permitted alteration or an extension.

The rule of thumb is if anything goes further to the front of the house then it is not permitted development. (unless it is a porch and adheres strictly to the rules around that)

[Roxiet2013]

OK. So to get this right because I want to change the roof on something to the front of my property it would need planning permission?
The area of the garage isn't changing at all, it's just the 2m bit of flat roof on top of it (the rest of the garage sits within the house under a bedroom) would be changed to a slope.
Planning laws are very confusing!