Hello,
I will be pouring a concrete slab for a spa with a 91" X 91" footprint. Though I know that it has to be 4" thick, I am not sure what the total size of the slab needs to be. I already have had the electric installed where it needs to be (about 7" in from the front of the slab); so it needs to be that much longer, plus the required distance from the electric souse location to the actual spa. Also I will be building an enclosed wood deck around the spa, so there will be no need for concrete steps. I am guessing 10 X 8, but I'm not sure. I live in Los Angeles County and would love some advice.
Also, do I need to include a measure of gravel below the slab for drainage? My soil is hard clay.
Thanks