What would be the easiest way to avoid puddling under a slab?

What would be the easiest way to avoid puddling under a slab?

• A. Careful grading
• B. Increase cement content
• C. Use larger aggregate
• D. Add water after placement

Answer: (A)

Avoiding puddling under a slab comes down to how the ground underneath is prepared. The easiest fix is careful grading of the subgrade so the surface has a uniform slope away from the future slab and no low spots where water can pool. When the subgrade drains and stays dry, the base materials stay stable and the concrete has solid, even support, reducing the risk of settlement and cracks later on. Adding more cement, using larger aggregate, or adding water after placement don’t address the drainage issue and can cause other problems (excess moisture, altered strength, or improper finish).

Avoiding puddling under a slab comes down to how the ground underneath is prepared. The easiest fix is careful grading of the subgrade so the surface has a uniform slope away from the future slab and no low spots where water can pool. When the subgrade drains and stays dry, the base materials stay stable and the concrete has solid, even support, reducing the risk of settlement and cracks later on.

Adding more cement, using larger aggregate, or adding water after placement don’t address the drainage issue and can cause other problems (excess moisture, altered strength, or improper finish).