I have controversial views on extensions and don't always agree with extending a house to include more and more bedrooms when the infastructure on the street outside can't handle the growth of the house and it's occupants. For instance, next to me was a very generous size three bed house (same as mine) it now has five beds, as well as extra reception rooms and bathrooms. We live in a very pretty cul-de sac with private garden in the middle, this house is now a carbuncle (IMHO) on the street and houses a family of four boys that are all hitting driving age, can the street/drives handle a possible six cars?
Although I do see the need for more housing so I suppose it's greener to extend than build more and more larger houses in rural areas. I also understand that ir's cheaper to extend than it is to move.
Flame suit on.....