How to fix a cracked foundation holes

Cracks or fissures in foundation walls and falling mortar between joints may be attributed to various causes. Cracks between mortar and the material to which it was originally bonded may be caused by shrinkage of the mortar during setting, or soon thereafter, or by the expansion of mortar through saturation. Often the volume change of the mortar is greater than the material to which it is bonded and this change sets up a movement that destroys the bond.

If the walls are built on ground that will not support an equal weight at all points, uneven settlement may cause cracks to develop. An underground spring or flowing water under one corner or section of a foundation may produce similar results. Small cracks thus started may become larger in time from action of the weather and other forces.

Frost has a tendency to attack weak spots. Expansion and contraction caused by extremes of heat and cold increase the damage, and water seeping through the cracks gradually wears away the material, causing it to crumble and fall apart. The disintegration is generally more rapid in mortar joints.

Results of such disintegration are far reaching and if not remedied may cause further damage not only to the walls themselves but to the structure they support. A basement will probably become damp and unsanitary if these inlets for moisture are not closed.