Owain wrote:

| As regards changing the roof from a hip to a gable - would
| that require planning permission as well as the building
| regs?

| Almost cetainly.

And is quite likely to be refused as the OP is in a semi, and the planners
are likely to be unhappy about changing the shape of one side but not the
other.

I think it depends on the area you're in. I've just done exactly this -
a hip to gable conversion - with no problems at all from Harrow council.
My architect, however, told that if I'd have been in Brent or Ealing -
neighbouring councils - he would have been most suprised if planning
permission had been granted. On the downside though, they did insist
that the back wall of the dormer was 100cm up the roofline, and that the
edge of the dormer near the gable end was brought inwards 100cm as well.

Regards
Paul