Skokie is one of the older suburbs of Chicago, having been settled in the 1850’s and incorporated in 1888. Today it is a fully-developed residential and commercial suburb with a population of 66,000 living in nearly 24,000 homes.
Most of these homes in Skokie have basements of poured concrete and, as in neighboring suburbs like Evanston and Wilmette, these basements can be a source of aggravation for homeowners. One very common problem is the occurrence of cracks in foundation walls which, depending on their placement and severity, can indicate one or more of several issues.
It is particularly important for Skokie homeowners to be cognizant of cracks in basement walls because of the age of their homes. Not surprising, given Skokie’s long history, more than 60% of the homes there were built before 1960. With older homes, although initial settlement has been long completed, foundations have been subjected to decades of stresses and pressure from outside soil that will eventually cause cracks.
Newer homes are also subject to foundation cracks, especially given the recent drought and the reasonably rainy year that followed. Cracks can be caused by settlement or sinking of foundations or by pressure from over-saturated soil against the foundation walls. No matter what the cause, these cracks present a problem that can’t be ignored.
Why Skokie Homeowners Can’t Ignore Basement Foundation Cracks
Cracks in Skokie basement walls are either structural or non-structural. Here’s the difference:
Non-structural cracks do not threaten or impact the integrity of the foundation. They are generally narrower than structural cracks, typically less than 1/8” and do not necessarily form identifiable patterns. These cracks can be the source of significant seepage and result in wet basements.
Structural cracks are much more serious and affect the stability of the home’s foundation. These cracks are wider than non-structural ones and are typically seen in patterns — one more-or-less vertical crack in the center of the wall, with angled cracks across the top corners. Usually invisible from the inside are vertical cracks at the corners where the damaged wall meets the adjacent walls.
Left unrepaired, these cracks will continue to widen, separating the foundation wall from the aboveground structure, causing cracks in exterior and interior walls and destabilizing the entire home.
So, what is the Skokie homeowner to do about these cracks?
Seepage from non-structural cracks can be stopped by injecting the crack with expanding polyurethane from the interior. The polyurethane fills and seals the crack all the way to the outside soil and remains flexible once it has cured so that minor foundation movement in the future doesn’t cause the crack to re-open.
If the basement has been finished or the crack just can’t be reached from inside, it can be repaired on the exterior with sodium bentonite clay, which forms a pliable permanent barrier against water intrusion.
Structural cracks require a more extensive repair. If the problem is diagnosed before the affected walls have moved inward more than about two inches, the cracks can be repaired and the foundation stabilized by applying super-strong carbon fiber strips to the wall in a number and placement determined by engineering data.
If more significant movement has occurred, it will require the use of steel channel bars, secured below the basement floor and tightened between floor joists above, to stabilize the wall and prevent further movement.
Either method requires no maintenance and is less intrusive than steel I-beams or plate anchors; both can be covered by a normal 2x4 stud wall if the basement is to be finished.
When a Skokie homeowner spots a crack in a basement wall, he or she will need the expertise of a foundation repair contractor to diagnose it and recommend a repair. At U.S. Waterproofing, our foundation repair experts use engineering data to recommend and implement the least intrusive and most cost-effective structural repairs and our basement waterproofing team has permanently repaired thousands of non-structural cracks using the most modern and effective methods. Why not ask for our free advice when those cracks crop up?