How to tell if builder put rebar in foundation

[lkage (Larry Kage, CMI)]

@kbrose

I have a fairly paranoid extended family member who is currently having a home built. They are concerned the builder may not have put rebar in the foundation. Anyone have a creative trick I could use to help get them some piece of mind. I’ve thought about trying to use a strong magnet…

I’ve never tried it, but there is this:

Locating Rebar in Concrete