Symptoms
- Water on the basement floor during or shortly after rain
- Wet spot along a wall or at the floor-wall joint
- Problem worse in heavy or prolonged storms
Likely causes
- CommonPoor grading letting water pool against the foundationSoil sloping toward the house channels rainwater right to the wall.
- CommonClogged or misdirected downspoutsRoof water dumped near the foundation overwhelms the soil and finds its way in.
- PossibleCracks in the foundation wall or floorWater under pressure from saturated soil can seep through even small cracks.
- PossibleHigh water table or hydrostatic pressureIn some areas groundwater itself rises enough to push through the slab or walls.
What to do
- Note exactly where water first appears and whether it follows a wall, a crack, or comes up through the floor.
- Check outside for grading that slopes toward the house and downspouts discharging near the foundation.
- Extend downspouts to carry water at least 4–6 feet away and regrade any low spots close to the wall.
- Clean gutters so they aren't overflowing and adding to the runoff near the foundation.
- Inspect the interior wall and floor near the entry point for visible cracks and seal small ones with hydraulic cement once dry.
- Move stored items off the floor and use a wet/dry vacuum or fan to dry the area and reduce mold risk.
- Have a waterproofing contractor evaluate if water keeps entering after drainage fixes, since an interior drain system may be needed.
Tools and parts
- Wet/dry vacuum
- Shovel
- Flashlight
Downspout extensionSearch: “downspout extension kit”
Hydraulic cementSearch: “hydraulic cement crack filler”
When to call a pro
Call a waterproofing contractor for persistent leaks after fixing grading and gutters, especially if water rises through the floor.
Safety
Use caution
Turn off electricity to any outlets or equipment in a flooded area at the breaker before working near standing water.