How Water Infiltrates and Damages a Home's Foundation

Water finds its way into your foundation through several weak spots. Cracks from settling or temperature changes are the most obvious openings. Even hairline fractures can let moisture through, especially during heavy rain or snowmelt.

The joint where the foundation meets the walls is another frequent entry point. Poured concrete is somewhat porous, so water can slowly migrate through it. Poorly sealed windows, utility lines, and drainage gaps also allow water to work its way in.

• Cracks in the concrete or block walls
• Gaps around pipes and wiring penetrations
• The seam between the foundation and the sill plate
• Unsealed window wells or basement windows
• Poorly compacted soil that directs water toward the wall

You may notice damp spots on basement walls or floors, a musty smell, or peeling paint. Efflorescence, a white chalky residue, often appears where water evaporates from concrete. Cracks that grow wider or new stair-step cracks in block walls are red flags.

Wooden components like sill plates and floor joists can rot when they stay wet. You might also see rust on metal supports or fasteners. If you spot any of these signs, address the water source quickly to prevent more serious structural problems.

A sensible defense is keeping water away from your foundation. Clean gutters and downspouts that direct water at least six feet away. Grade the soil so it slopes away from the house. Seal any visible cracks with a high-quality concrete patching compound.

Inside, keep the humidity in check and fix any plumbing leaks immediately. Pay extra attention during snowmelt and heavy rains, as those periods bring the most water. For persistent issues, foundation waterproofing can add a protective barrier. If water has already entered, extraction and drying are essential steps.