Drainage for floating slab
We have a nearly level site with a layer of clay below about a foot of topsoil, such that we’ve measured water less than six inches below the surface in the Spring.
Where would you install drain pipes for a floating slab that has only 18 inches to work with (see drawing)? We were planning on installing a second set of drain pipes closer to the surface to take the gutter water. There is very little slope across the property so draining to daylight will be difficult. Do you think we need the double exterior drains?
Shouldn’t we install interior drains under the insulation to relief any hydrostatic pressure? How deep should they be placed? I assume they should drain to daylight too.
I want to insure that this slab will stay dry.
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