The Unstoppable Movement Of The Earth
Generally speaking, we like to think of the ground as something solid and stable, at least so long as an earthquake isn’t shaking things to pieces or a volcano isn’t firing tons of ash and rock into the air. However, the dirt beneath our feet is constantly moving around thanks to wind, water, and daily changes in temperature.
Every year as the average temperature goes up and down, the ground contracts and expands thanks to the moisture in the soil. Concrete blocks like sidewalks are small so that there’s room to accept this changing pressure, but even so they will gradually tilt and crack as the ground beneath them moves and the weight of the block shifts away from the center of mass.
Soil consistency and location can change over the course of decades, too. For instance, the soil surrounding a valley will very gradually fill that valley in as years of rainfall carry dirt and mud downwards. After several dry years, soil will lose its moisture and shrink, and of course if annual rainfall goes up the soil will expand as it saturates with water.
The concrete slabs which form the base of every residential home are reinforced with steel, but at the same time they are poured out as a single massive block in order to keep moisture out and to better hold the weight of the building above it. Even if the construction company perfectly compacted the fill soil before building the foundation (and this step is not always guaranteed), the slow but steady changes in soil conditions can create voids beneath the slab, causing it to settle unevenly and crack. This is especially common in drought years when the soil contracts, and it can also happen because of a leaky pipe slowly washing the soil away from the location of the leak.
The slow movement of soil can also impact your foundation in other ways. If the ground in general is moving in a particular direction, it can cause the walls of your basement to bow inwards from the pressure, or it can move your entire foundation out from underneath your house. These aren’t as common as cracks in the base thanks to modern construction techniques and geological tests, but they can still happen.
Cracks in your concrete foundation are inevitable, but not every crack is worth the effort it takes to repair or replace the whole thing. Even if the cracks are letting in water or even radon, there are ways to redirect them safely away from your home without going for the most expensive option.
Still, if you find yourself in need of professional help or advice, and if you live in or near the state of Maryland, give AA Action Waterproofing a call. We’ve been dealing with cracked and leaking basements, crawlspaces, and foundations for over 27 years, and with a free in-home estimate we can help you figure out just how much repair work your home really needs.