> Our house is on a slab.

My first house was that way and I had the same issues with the "what if" a pipe bust under the slab.

House I've been in now for 20 years I designed. All brick exterior, lots of insulation, and on a 4 foot fully lit, closed (no vents) and heated and air conditioned crawl space fully sealed. Crawl still looks new under there, and A/C equipment that has had to come out and be changed one time had the installers saying the 16 year old one looked like it just came out of the box. No dust or bug problems.

Then again, I even put hurricane tie-downs on the roofing. So I was out to stop crap from happening.