Newbie here... thanks in advance for suggestions. We are building a new house with a Metwood steel floor with 4" of concrete with hydronic radiant heat. The garage will be a zone and I want to separate it from the main house. What are the options for a thermal break in the concrete between garage and main house? The garage and main house are elevated with a full finished basement below. Thanks, Dean

I think it is code to have a step down to the garage so gasses would settle to the lowest point.

Will there be any "living" space below the garage floor?
If you want to go with something a bit more industrial than simple expansion joint filler...

https://www.schock-na.com/en-us/slab-edge

Your other option is to simply insulate the garage slab as well.
Then all you need to thermally break is the side of the garage that abuts the driveway.

Yes, the garage will be insulated, but I may not want to always heat it, so I was thinking if I had a thermal break in between then I would have options and it would not affect the main living space if I decided to not heat the garage space..

Yes, the garage will be insulated, but I may not want to always heat it, so I was thinking if I had a thermal break in between then I would have options and it would not affect the main living space if I decided to not heat the garage space..

I don't think the step down into the garage is a code requirement. It is more of a best practices thing.

We did a over under garage with pre-stressed concrete and ICF walls so thermally isolating them was easy.

What area do you live in? We are in Michigan.

We are having a hard time with garage door openers not shutting the door all the way to the floor and leaving a gap that cools the garage severely. Even though the garage is R30 insulated it doesn't matter when the garage door stays open 3/8's of a inch.