DavidKendall wrote:
Want to draw up some basic ideas for house extension - does anyone know of
any free CAD software that I might use to do this please?

I used vectorengineer pro-tools to do my extension plans, which were
passed a couple of months ago. I found it easier than the normal
auto-CAD style programs. You can download the quick tools version for
free, and it may be enough. It can't do hash patterns and dotted lines
though. Program has a few quirks. Biggest one - the dotted lines cannot
be scaled, so you have to chose a reasonable drawing scale to start off
with. I started off with 1:1 and had to convert everything to 1:10 so
that the dotted lines came out dotted.

http://www.vectorengineer.com/

Cheers,
Simon.