The village of Oak Lawn can trace its history back to the early 19th Century but truly came into being in 1859 when the newly formed Worth Township financed the construction of Black Oak Grove Road, now known as 95th Street. This thoroughfare began to draw residential and commercial development that led to the formation of the town.
Oak Lawn was incorporated in 1909 and began to develop its civic infrastructure, including a village hall, fire department and library. Growth was slow, though and population barely topped 2,000 by 1930. Development in Oak Lawn was jump-started in the mid 1940’s when, like in other burgeoning suburbs around the U.S., veterans returning from military service in World War II flocked to the outlying areas to raise families and establish their lives.
Today, Oak Lawn has a population of 57,000 and is a booming commercial center in Chicago’s southwest suburbs. Families there live in more than 22,000 homes, nearly three-quarters of which were built between 1950 and 1980. Homeowners there are discovering the maintenance and repair problems that go along with aging homes and many of them have found basement foundation cracks and are wondering what can be done about them.
Basement Foundation Cracks in Oak Lawn Homes
Basement foundation cracks are either structural or non-structural and homeowners will be able to distinguish between them in most instances.
Structural cracks are normally wider than one-eighth inch and usually follow a pattern. In a poured concrete foundation wall, there will typically be a vertical crack in the center of the wall and two angled cracks across the upper corners. Not visible from inside are two more vertical cracks, these at the outside corners where the damaged wall has begun to separate from the adjacent walls.
In a masonry wall, such as concrete block or brick, the cracks will follow a stairstep pattern that usually leads to a bowed or bulging area in the center of the wall.
A non-structural crack does not threaten the integrity of the foundation but usually will allow water to seep into the basement. These cracks are typically narrow, less than one-eighth inch, and do not fall into any discernible pattern. They often originate from window and door openings or near the bottom of the foundation wall.
Repairing a seeping non-structural crack is best done by injecting the crack with expanding polyurethane from inside the basement to fill and seal the crack all the way to the outside soil. The polyurethane remains flexible when cured to prevent re-cracking from minor foundation movement.
If the crack is unreachable from inside it can be repaired on the exterior with sodium bentonite clay to form a waterproof barrier against the crack on the “positive side” of the foundation.
With structural cracks the repair is not focused on the crack itself but in stabilizing the wall in which it appears. A foundation wall that has been pushed inward by lateral pressure from over-saturated soil can be stabilized by applying carbon fiber strips to the wall with epoxy if the wall has moved less than 2 inches. Further movement requires the use of low-profile channel steel for the same purpose.
When the cracks indicate that foundation has sunken or dropped, it is repaired with hydraulic push piers, which are installed at intervals to raise the foundation back to level and stabilize it there.
Regardless of the type of basement foundation crack, an Oak Lawn homeowner who finds one (or more) in his or her basement will require the assistance of a foundation repair professional and/or a basement waterproofing contractor. At U.S. Waterproofing, our team of foundation repair experts employs engineering data and state-of-the-art practices to repair and stabilize damaged foundations and our basement waterproofing experts rely on 57 years of experience to keep basements dry, permanently and cost-effectively. Why not ask for our free advice?