Floor cracks can seem very scary at first; after all, your home’s entire weight is supported by its foundation, and a cracked floor is a sign that something may be very wrong. So, it’s easy to overreact and think that your whole house is collapsing, or that you have to remove and repour the entire concrete floor. The thing is, floor cracks aren’t all that uncommon, especially here in South Florida.
Concrete floors typically crack when the soil below the slab is no longer able to support its weight. This happens for several reasons, including soil compaction, washout and shrinkage. The problem can go beyond the mere aesthetic too. That’s because, as concrete floor slabs settle, they can cause problems elsewhere in the home as walls begin to separate from floors or ceilings. In addition to visible wall gaps between floors and ceilings, signs of slab settlement can include cracks appearing at the corners of door and window frames.
Options to Avoid
Because foundation floor cracks can seem so unsettling at first, you may be tempted to fix the problem by either replacing the entire slab or by simply re-leveling it. The truth is, neither option is ideal.
- Slab Replacement: When you replace your slab, the original concrete must first be jackhammered into small pieces and carried out by hand. This is a seriously disruptive and expensive process that requires the removal of all furnishings, floor coverings and interior walls. Then the new slab is poured and allowed to cure for up to two weeks. In addition to the cost and disruption, this approach does nothing to address the reason why the slab sunk in the first place.
- Slab Releveling: Releveling the slab involves pouring a self-leveling grout onto the existing slab. If the surface isn’t prepared perfectly, the grout may fail to bond properly, which can cause chunks to break off over time. In addition, the grout adds significant weight to the slab, which can cause further settlement. Plus, as with slab replacement, this option does nothing to address the cause of the problem.
What Caused My Floor to Crack?
As mentioned earlier, slab floor cracks can happen for several reasons, all of which are related to the soil underneath your home. In each instance, the soil is no longer able to support the considerable weight of the concrete slab and the home that rests upon it.
Dry Expansive Soil
HVAC (Heating, Venting, and Air Conditioning) systems may be installed beneath the floor slab. Over time, the ductwork can leak air, drying out the soil and causing it to shrink and form voids into which the floor slab can crack and sink.
Soil washout is usually caused by plumbing leaks. If the leak is severe and there is a path for the water to flow, it can wash soil out from under the slab. With a void underneath the floor, there’s nothing supporting the concrete slab anymore. In time, it begins to crack and sink downwards.
When your neighborhood was built, the developer likely moved soil from higher elevations to lower lying areas to create a consistent grade. This soil, known as fill soil, is often not as compacted as the native soil that existed there for thousands of years. So, when your home was constructed, its footings may have been set below this weak fill soil to avoid a foundation settlement issue. Unfortunately, the slab may have remained on the weak fill soil. This compressed and settled and a void was formed under the slab. In time, it cracked, broke and settled into the void.
Diagnosing and Fixing the Problem
Instead of simply addressing the symptom — the cracked slab — NSquare recommends fixing the problem permanently. This can be achieved by connecting the slab to load-bearing soil or bedrock via a piering system or by using high-density, lightweight expanding PolyLevel foam to raise settled concrete to its original position.
Your Free, No-Obligation Inspection
Our project consultants are trained to expertly diagnose foundation problems. They use highly specialized equipment that allows them to develop a solution tailored to your home’s unique needs. By the time the inspection is over, you’ll know exactly what caused the problem, exactly what it will take to fix it permanently and exactly how much it will cost to do so.
Once a solution has been customized for your home, we pick a date for the job. At that time, a highly trained crew of technicians will install the solution, leaving your home fixed and protected for future generations — restoring its value, improving your family’s quality of life and giving you lasting peace of mind.
The Cost of Doing Nothing
Once you get over the initial shock of discovering a floor crack, you may be tempted to throw a rug over it and ignore it. After all, your house is still standing. And the crack looks as if it’s only growing an inch or so a year, so you’ve probably got plenty of time to take care of it, right? Well, it’s true that floor cracks can grow at a slow rate, but as mentioned earlier, they are usually an indication of a more serious structural problem occurring below your home. Most important, no matter how much you hope or pray or ignore them, foundation problems don’t get better with time.
But even if you do accept foundation problems, they can cost you serious money when it comes time to sell your home. Depending on the issue, foundation problems can force you to discount your home by up to ten percent or more at sale time. For a $300,000 home that’s $30,000. For a $750,000 home, that’s $75,500! As you can see, the cost of repair often pales when compared to the cost of doing nothing.
And this is your home we’re talking about. It’s where you and your family live, lounge, love and laugh. Don’t you owe it to them to make sure it’s as structurally sound as possible? Of course you do.
One last thing: Because foundation problems don’t get better with time, they’ll never be less expensive to fix than they are today. So why not address them now? You know you’ll have to sooner or later.