"Grahammazy" wrote
| ... update it to either a double glazed window or maybe even
| patio doors which would lead out to my garden....
| 1) Do we need planning permissions or building warrants for any new
| windows or patio doors (the latter would require us to have 2 - 3 steps
| built outside as well)?

You probably do not need planning permission, unless you are in a
conservation area etc. or the window is on a boundary. It might be wise to
get written confirmation from the council that PP is not required, in case
of query later.

For replacement windows, you either have to have the work done by a FENSA
certified contractor, or DIY or use an unregistered contractor, and get a
building warrant.

For changing to a door, you will require building warrant.

| 2) If we went for a window, I presume as the space is so big it would
| have to be along the lines of the current layout ie 2 small windows and
| one big one in the middle? Is this possible with double glazing? Most
| d-g windows I have seen are just one individual window.

Depends on the structural arrangement. It might be possible to move the
'mullions' and have three more-equal sized windows. Big windows will be
disproportionately more expensive because they are awkward to make and
install.

| 4) Would getting patio doors be a much more expensive option (as there
| would be more building work to form the hole required fopr them and
| then fill in at the sides etc)?

The more work is done, the more the cost, but patio doors might increase the
value of your property if they improve access to the garden.

Owain