making garage bigger

[suzuki 650L]

I have a 16 x 20 garage and want to double the width to 32 x 20. I do woodworking and work on my own truck and bike. It is a slab with a 4 " raised curb. I do not mind leaving the 4 walls up and just add to them because of the wood dust from the woodworking. I am just wondering if it would be a problem with 2 slabs and 1 roof. I'm in central IL. , so the winters can be cold. I am guessing if it would heave up the building would be damaged. I just dont know if it could happen. I know two different kinds of foundations can heave. I dont have the money to tear down but could really use the space to keep from laying in the driveway. I guess I'm asking if anybody has any input on the idea? Thanks for any help.

 

[77thor]

It won't be a problem if done correctly. The key is the footings for the addition.
I had a third stall added to my attached 2-car garage about 5 years ago, same situation as yours.
BTW; I live in Wisconsin.

 

[suzuki 650L]

If it is the same as the garage then it should work out. Thats good. I'm thinking about putting 2 x 10's for the rafters and adding a hip wall of 2 or 3 foot for a little extra storage.I'm not sure if that will work but dont see any problems with it. I'm thinking 2 x 4 walls should hold it up, I would make the new side with 2 x 6's for the extra insulation.

 

[D45]

Attached garage?