New member with new garage built

[Masava60]

Hello all,
New member here. Very happy to have discovered this site as its full of great information. I live in central VA and have begun my detached garage build. The garage will be 50x32; 36x32 inside with a 14x32 carport on the side. Garage will be built on a 2.5’ grade. Foundation with CMU stem wall, floating slab, stick build, 10’ walls, brick and vinyl exterior to match my house. Attic trusses used in half the garage, scissor trusses in the other half to accommodate a car lift. Got to have more room to work on my track car (Boss 302) along with other projects. The missus is a quilter and I need to build some her some quilting tables. My house’s attached garage is woefully inadequate. I’m recently retired and my son is a framing contractor, so we’ll be doing the majority of the work ourselves.
Current status: foundation, cmu stem wall, grouted with anchor bolts all complete.
Next 30 days pour floating slab. Need to rough-in PVC sleeve for water supply, PVC drain for sink, (no toilet), fill with #57 stone, treat for termites, insulate between slab and stem wall, 4’ x 2” insulation in from walls, vapor barrier, etc., and pour the slab.

I’ve had lots of questions, as building garages is not my forte, and this site have been very helpful in answering these question.

Thanks all,
Mark

 

[billconner]

Nice. Doing sort of similar with cmu stem walls and stick frame building. At the footing right now with blocks on site.

 

[nadogail]

Welcome to the Forum from the shore of San Diego Bay. Your pictures look very good and I wish you well.

 

[Jayman17]

Welcome, looks like you are off to a good start. I hope your project goes off without a hitch.

Jay

 

[Toolfool]

Welcome. Keep the pictures coming.

 

[Masava60]

Hello, need some guidance on the floor prep prior to the slab pour. As you can read above in my overall description, the build has a CMU block stem wall. Slab will float completely on compacted 57 stone; not be tied nor rest on door threshold block. I’m installing 2” thick insulating polystyrene foam around the perimeter. Since I reside in Virginia, I’m only installing 8” vertical foam on interior of stem wall and 2‘ horizontal foam as a thermal break around the perimeter. Do I need to do anything different at the garage door openings? My assumption is that I can install the same thermal break (8” vertical plus 2’ horizontal) at the openings without compromising the integrity of the slab. I’m concerned that the weight of the slab plus driving vehicles over the underlying foam will lead to problems. Let me know if this question needs to be posted in another thread for better response.

 

[billconner]

What kind of foam? Owens Corning Formular 150 has compressive strength of 15 psi, over 200 psf. The foam shouldn't be a problem as long as compacted stone base under is relatively flat.

 

[Masava60]

What kind of foam? Owens Corning Formular 150 has compressive strength of 15 psi, over 200 psf. The foam shouldn't be a problem as long as compacted stone base under is relatively flat.

PolyPro EPS. Specs say compressive strength is 12 to 17 psi. Thanks for the feedback.

 

[billconner]

Don't know what your details are like but my deep foundation is continuous under overhead doors with block stem wall. I poured a "sill" on it for garage door. Apron outside and floor inside "float". I'll pour floor a 1/2" higher with a galvanized steel edge so any rain or melt doesn't run in. I think a slab on grade that might move should not be restrained at walls, and should lessen shrinkage cracks.

 

[ConCretin]

Hello, need some guidance on the floor prep prior to the slab pour.

Take a look my Guide to Floor Slabs in the link below for an overview of the process. Unless you are installing radiant heat, insulation isn't really necessary or cost effective especially in your climate. in colder climates, it's necessary to keep frost from penetrating through the walls into the soil under the slab. It looks to me like you have a good plan, I wouldn't sweat the minor insulation details.