Outside Sources (bulk moisture) originates from surface water: Ice, snow, rain, fog, high humidity and surface run-off; and ground water: water in the soil.

Surface Water

Water runs downhill. Surface water that comes from rain and melting snow, coupled with poor grading around buildings, means it leaks into our basement or crawlspace. In some cases it causes flooding, in other instances it results in slow, hidden leaks with hidden damage and health effects. This moisture can also be moved by diffusion and/or capillary action.

Ground Water

The changing water table in the ground is based on seasonal fluctuations. In some instances a high water table, if not pumped down or drained away, can cause flooding in basements or crawlspaces. Even in instances where it doesn't cause flooding, it often means considerable moisture is being drawn into the home by diffusion and/or capillary action.

Bulk Water

The first rule about bulk water is that it runs downhill, not a profound statement but it seems to be endlessly forgotten.

It is important to:

• Do a proper job of grading around building to encourage water to run away from our buildings
• Look after eaves troughs and downspouts and the water that comes off our roofs
• Divert water that comes off of high ground to go around and away from our buildings

These are items that are often done improperly or are overlooked. If attention is paid to these, most of the bulk water problems will be resolved.

Water in Basements and Crawl Spaces

Water in basements in crawl spaces occurs from various sources:

• Moisture is released by curing concrete
• Moisture diffuses inward through improperly dampproofed walls and slabs
• Moisture is brought in by infiltrating humid air
• Water from surface drainage through foundation cracks, etc