Originally Posted by sbwolf
I need to construct a concrete pad for a hot tub. I need the top of the concrete pad to be 18" above ground level to fit into the deck plan properly. I plan to dig about a foot into the ground to avoid the majority of any frost heaving (we're 25 miles north of Philly, PA). I will use six inches of crushed stone that get compacted, but my question is, do I pour 24 inches of concrete, or somehow build-up the inner area and only pour the 4-6 inches that is recommended for the hot tub? Any advise?