Porch Extension - Walls

[Augustus]

I have planning permission for removal of existing porch & construction of a new 2 storey extension (on front of house).
For a number of reasons - I've decided to stick with what I've got and extend the existing stone, pitched roof porch out sideways to accomodate a small cloakroom. This will still be well within the footprint of the original planning permission so I believe there should be no planning issues there.
My main concern is the construction of the existing walls of the porch - they're just a single stone skin which, may or may not, be sufficient in terms of energy performance for a porch but once I've extended it out and put in a bog, it's no longer a porch & I'm guessing there will be building control issues.
I could do the new extension walls single skin as per the rest of the building & and provide some internal insulation in the bog & leave the rest as is. Or are they likely to insist on insulation throughout the structure now it's not really any longer a porch?
Perhaps, since it's a single storey structure with a pitched roof the single skin walls are ok as they are & the roof could be insulated?
Anyone had any experience of this kind of thing?

 

[theprinceofdarkness]

it sounds as though you want an "outside" loo attached to the house. Other then freeze ups I don't think you need insulation. But if this uninsulated volume intrudes into the main house, then the BC will be very interested.
Frank

 

[Augustus]

But if this uninsulated volume intrudes into the main house, then the BC will be very interested.
Frank

It does indeed intrude into the main house. There is no secondary door between the kitchen and the porch (I guess one could be fitted). It was there when I bought the place 13 years ago. It's a very old property but the porch looks a relatively recent addition. Maybe it was added before there were such stringent energy efficiency criteria. Or perhaps they didn't get BC in.

 

[theprinceofdarkness]

Can you get an insulated floor in this area ?
Frank