We're considering building a bedroom & bathroom above our single garage/utility room. We've had prices for plans and know council fees. We're digging down to check what the foundations etc are before we go ahead with having plans drawn.I'm interested to know how much people have paid and what they had to do to the foundations. My dad is in the building trade and has extended over their garage so I have a good idea of cost but they were lucky that their foundations were good so able the support the 2nd storey.
We dont know yet. We know a surveyor who has said that because the garage and house were build at the same time that the garage probably has the same foundations as the house. My parents live in a similar house which was built around the same time and their foundations were ok to hold the second storey. They just had to build up the single skin walls of their garage. We wont know until we dig down.
Building over an existing single storey structure can be very expensive because of the difficulties in modifying the walls, foundations, removal of the roof, etc.
Silly as it sounds, it might be cheaper and quicker to demolish and rebuild but this would depend on lots of different factors.
I have only ever done one job similar to yours when I was on my 'Part 3' (i.e. 7th and final) year of training. I was working for a practice that didn't really like small domestic jobs and it was a favour for one of the partner's cronies, so the rule was minimum fees and maximum pressure on the cheapest member of staff - me.
As the Assistant I was nervous of upsetting anyone and very conscious of my lack of experience so I actually put a lot of effort into the drawings.
Neeless to say I was quite annoyed / embarrassed when the builder told the client - and he was right - that it was easier to demolish and rebuild!