I have a detached garage that is about 8 feet away from my house. Currently there is a breezeway connecting the two. In the next few years I would like to close in part of that space to make a mudroom that's about 8x15. This mudroom would be heated and finished like any other room in the house.

Even though I will most likely run my ideas past an architect when the time draws near, I like to have some background knowledge about the project.

What type of foundation will work for this small room? Will I be able to use a slab foundation like the one that is in my garage? If so, how deep will the slab have to go? BTW, I live in southern New York.

Thanks,
Logan

We do not have enough details to make a guess. Your garage is a slab but what is under the breezway now and what kind of foundation does your house have. The loocal building department can easily tell you what they will and will not allow. From what we know so far your house and your garage move at slightly different rates if their foundations are different. What is your frost line in your area, 48"?

Frost line in my area is 48". The house is on a cinderblock foundation that goes down 8'. The same slab that's under the garage extends under the breezeway.

You just answered your own question. If you already have two slabs and there isn't significant movement you just use the slab you have. However, your building department may have regs that will specify something else. Have you pulled a permoit or talked to the building inspector yet?