
We eventually decided against it and got a summerhouse (i.e. a shed with a veranda) in the back garden instead but not before I had (very inexpertly) doctored an image of the house to see what our ideas would look like.
At the time, Mary wanted to do something like this:

and I thought something like this looked nicer:

Looking at them now, I prefer Mary's idea - I guess I didn't want to have the same dimension rooms in the new part of the house. Anyway it didn't happen but the idea never really went away and resurfaced in Summer 2005. We went to an architect who advised us to go for something similar to the second idea (above) because it was in keeping with the original building and it would be easier to get planning permission. We agreed and he drew up the plans (Plans - Page 1, Plans - Page 2), which I think are way nicer than the other two ideas (especially inside).
We got planning permission easily enough - one small hiccup delayed it for a month. The architect had originally included 'the installation of a PuraFlow system' in the planning notice and the county planner queried this, saying it wasn't necessary. Not the architect's fault - the law's wording is very vague so it was hard to know how it applied to an extension. If it was necessary and it wasn't in the application, planning would have been refused and we'd have to re-apply and wait another 3 months.