Crack in foundation

… or dirt floors, or stone rubble foundations, sump pump pits…

More information if this helps.

http://home.howstuffworks.com/radon1.htm

Marcel:) :slight_smile:

The only time I worry about a concrete crack is if it’s wide enough to swallow my loonie . That’s a dollar coin for all you not familiar with Canadian currency. Doug

thanks for all the input, the site references are great !!