I'm planning to build a 20x10 shed on my property, which has really poor drainage due to heavy clay soil. My idea is to dig a foundation filled with aggregate and install a French drain that runs to a sump pump basin. The drain would go along the length of the building, placed in a shallow 'V' shape at the center of the foundation to direct all water toward the pipe and out to the sump pump. I'm wondering if I should consider running the French drain around the entire building instead. Thoughts?
2 Answers
I’d be cautious about draining water underneath. If that drain clogs up, it could really cause issues. I’d recommend building up the area where the shed will sit, making it higher than the surrounding ground, then directing water away from it with dirt instead. I tend to favor surface drainage over buried pipes, unless they’re deep enough to avoid freezing and can drain out properly.
The main concern with your plan could be cost and effort. If by foundation you mean the aggregate slab, doing the drain under it might require more work than just running a perimeter drain. You should also think about where the water is coming from—whether it collects in low spots or just doesn’t percolate well. If you're facing serious drainage issues, though, this might still be worth considering!