Sidewalk Slabs Don’t Last Forever, And Neither Do Foundations
If you’ve ever walked anywhere (and probably even if you haven’t), you know what a sidewalk slab is: it’s a block of pale gray concrete a few feet wide and long and a few inches deep, it sits on a substrate of gravel and sand, and it gradually sinks, cracks, and otherwise falls apart as the years go by.
There are numerous reasons why sidewalks don’t last forever. Despite the gravel substrate providing excellent drainage and despite the fact that sidewalks are broken into individual slabs for a reason, water can infiltrate the concrete and cause it to expand or contract with the temperature, particularly when it drops past the freezing point. The gaps between each slab give them room to expand into when necessary, but sometimes a slab will crack anyway. Asphalt has the advantage of tar to make it a little more waterproof and a little more flexible, but every kind of manmade stone cracks eventually.
At the same time, the earth itself moves slowly but surely as the years go by, and what was once level ground beneath a sidewalk can push up, sink down, or even move from one side to the other, taking the slabs with them. The weight of the traffic that uses the sidewalk also has an impact, as do the grasses and weeds that grow in the cracks between and within the slabs.
The factors that affect sidewalks also affect foundations, although not quite in the same ways. Foundation slabs are very big and very thick, which means that the forces needed to crack or move them also have to be much bigger. Basement foundations also have the advantage of existing underground where the earth isn’t quite as unstable as the surface, at least depending on plant and water conditions.
Still, the earth has the power to crack even the largest and strongest of foundations eventually, making the question less an “if” and more a “when.” It also doesn’t help that the earth rarely settles evenly, which means that one corner will often sink below the rest and the foundation block will crack and break off in order to fall into the gap. This means that the walls and floor which rely on the foundation will also warp slightly to accommodate the change.
While you can afford to ignore some minor hairline cracks here and there, early intervention is always less expensive than more drastic options like complete foundation slab replacement. If your property is in Maryland or a nearby state and you need an opinion about your foundation, contact AA Action Waterproofing for a free estimate. We’ve been in business for over 27 years and we haven’t seen a project we couldn’t handle.