Water and soil cause other problems, too. Consolidation or settling of subsoil due to heavy rains, or a substantial loss of moisture in the soil, can undermine the foundation from below. This settlement may allow footings to drop, causing vertical and step cracks as well as tipped and cracked concrete floors. In some cases, this kind of settlement causes the walls to tip outward.
Look for problems outside the foundation – The first approach to fixing a wet basement is to correct the grades around the foundation so that water flows away from the walls. Make sure downspout drains, sump-pump discharge pipes and storm sewers convey roof and surface water away from the house. Low spots around the foundation are likely to collect water, so any depressions should be filled. (For span at least two joist bays to provide lateral restraint. Again, wood I-joists require additional bracing.
For lateral support at the bottom of the wall, each column should have a welded-steel plate, which is bolted into the concrete slab or footing. Any spaces between the wall and column can be filled with ~ mortar grout. If there are pipes or conduit on the walls, they can be accommodated by notching the face of the column to fit over the obstruction, although the notch should be limited to a depth of 1 in. Ductwork along the basement ceiling can be bypassed by welding a horizontal leg to the top of the column at the wall, and then a vertical piece to fit along- side the joist beyond the duct.
Walls displaced more than 1 in. must be excavated and re-plumbed – If water problems go unchecked, the accompanying season- al expansion and contraction of soil can wreak havoc on foundation walls, sometimes causing severe displacement. Building-codes may require any foundation wall displaced 1 in. or more to be excavated and jacked back to plumb