How do I detect if a part (or parts stuck together) are floating?

I have somewhat of an idea using rays and I was wondering how do I detect if a brick or multiple bricks are floating in the air? My problem is when I destroy a model that I made (its welded together) then the welds cause the parts to float. I have tried individually using rays per part and I have tried getting touching parts and couldn't figure out what to do. I know this sounds like a request but I have tried everything I can think of.