How much gravel do you put under a concrete pad?
In this regard, what kind of gravel do you put under concrete?
It should also compact easily and be evenly compacted before the concrete is poured to provide strength and stability. Recycled gravel is suitable for use beneath a concrete driveway as long as it is clean and uniform.
Subsequently, question is, what is the best base for concrete slab? Subgrade and subbase are the foundation of a concrete slab and play critical role in its performance. According to the ACI Code, the subgrade is a compacted and improved natural soil or brought infill whereas subbase is a layer of gravel placed on the top of the subgrade.
In respect to this, is gravel needed under concrete?
Whether you pour concrete for a walkway or patio, a strong gravel base is required to prevent the concrete from cracking and shifting. Gravel allows water to drain into the ground below. When packed tightly, however, the gravel doesn't shift beneath the concrete.
What do you put under a concrete slab?
Just scrape off the sod and topsoil and add gravel fill if needed. If you have clay or loam soil, you should remove enough to allow a 6- to 8-in. layer of compacted gravel under the new concrete. If you have to remove more than a few inches of dirt, consider renting a skid loader or hiring an excavator.