Start outside: gutters and downspouts
The most common cause is also the cheapest to fix. A single clogged gutter or a downspout that empties right next to the foundation can dump hundreds of gallons of roof water against one basement wall during a storm. Walk around the house during or right after rain. Gutters should not overflow, and every downspout should carry water several feet away from the foundation, not into a flower bed against the wall.
Check the grading around the house
The soil next to your foundation should slope away from the house. Over the years, soil settles, mulch builds up, and patios or sidewalks can tip back toward the home. When the ground slopes in, rain runs straight to the basement wall and soaks down along it. Many Woodbury and east metro homes have clay-heavy soil that drains slowly, which makes poor grading show up faster.
Window wells
Basement window wells collect water. If a well has no drain, a clogged drain, or no cover, it can fill like a bucket and leak through the window frame. Water stains below a basement window are a strong hint that the well is the problem.
Cracks and the cove joint
Water also comes in through cracks in the foundation walls or floor, around pipes that pass through the wall, and at the cove joint where the wall meets the floor. Water that appears along the bottom edge of the wall, right where it meets the floor, usually means groundwater pressure is pushing water in at that joint.
Hydrostatic pressure and a high water table
After long or heavy rain, the soil around the basement becomes saturated. The water pressing against the walls and under the floor is called hydrostatic pressure, and it forces water through any opening it can find. When a basement leaks even with good gutters and grading, this is often the reason. It is usually solved with drain tile and a sump pump rather than with sealing products alone.
What you can do now
- Clean gutters and extend downspouts away from the house
- Add soil so the ground slopes away from the foundation
- Clear window well drains and consider covers
- Note exactly where water appears and take photos during the next rain
Those photos help a contractor find the cause quickly.
When to call a waterproofing contractor
If water keeps coming in after the outside fixes, if you see water along the floor edge, or if cracks are growing, have a local contractor take a look. They can tell you whether you need crack repair, interior drain tile, a sump pump, or a combination.