My basement floods every time it rains heavily. Water comes in through the walls and floor. How do I stop this?
Basement flooding from rain is caused by water finding a path into your foundation through cracks, gaps, or hydrostatic pressure from saturated soil. The fix depends on the severity. For minor seepage through wall cracks, apply hydraulic cement to visible cracks from inside (20 to 50 dollars for a kit). For water coming up through the floor, the water table is rising above your basement slab during rain. A sump pump is the primary solution — if you do not have one, installing a sump pump system costs 500 to 1,500 dollars and is the most effective long-term fix. If you have a sump pump and it is not keeping up, the pump may be undersized, the discharge line may be clogged, or the check valve may have failed. Outside the house, improve drainage: extend downspout discharge at least 6 feet from the foundation, grade the soil so it slopes away from the house at least 6 inches over the first 10 feet, and clean gutters to prevent overflow near the foundation. French drains along the interior or exterior perimeter are the most effective but also the most expensive solution at 3,000 to 10,000 dollars.
