We live in a double brick, tiled roof home, and underneath the floor boards, there is access underneath and is about 750mm space tapering to not much space at all, but the house is about 400 sq metres, and whenever I open the man hole cover outside, I notice how cool it is under there.
So, air drawn from underneath would be a good way to cool the house, except I don't know how long it would take to use up all that cool air.
