Convert integral garage to living space v new build extension

rubble2

Bit of an academic question but would be interested in a comparison cost wise please.

We have an integral garage approx. 5.4 x 2.5 metres area with a bedroom above. In rough terms how would the cost of converting the garage to useable living space compare to the cost of a newbuild extension of the same dimensions? ( lets assume that the newbuild option would have a pitched tiled roof.)
House is about 20 years old.

Thanks.

Doozergirl

It doesn't even compare.  Easily 4 times the price to extend.  

I'll tell people all day long to convert an integral garage before building an extension.   They're an astoundingly expensive waste of space for most people. 

rubble2

Doozergirl said:

It doesn't even compare.  Easily 4 times the price to extend.  

I'll tell people all day long to convert an integral garage before building an extension.   They're an astoundingly expensive waste of space for most people. 

Thanks, I expected a significant difference but wasn't sure what the scale of the added costs would be. A number of people in the local area have gone for the garage conversion - I guess your answer explains why.

Thanks again

FreeBear

5.4m by 2.5m is 13.5m². The typical cost of building an extension to give you a waterproof shell is in the £3K-5K per square metre range. So expect to pay £40K-68K depending on spec and assuming no hidden surprises.

Converting a garage, something in the region of £10K should cover most contingencies. After all, you already have the expensive parts already complete (foundations, walls, roof, etc). So the £10K budget is just for the frills and a bit of insulation where required.