Why should you be repairing cracks in your concrete block foundation? Because foundation cracks are the result of existing issues, or they can lead to larger structural issues themselves. This article talks about two different types of cracks you may have in your concrete block foundation. We don’t leave you in the dust either. We also tell you different ways professionals repair cracks.

Why You Should Be Repairing Cracks In Your Concrete Block Foundation

If you have cracks in your concrete block foundation, it’s a sign something is affecting the structural integrity of your home. If you leave those cracks alone, you risk your family’s safety. You don’t want your foundation walls collapsing when you’re sleeping. Cracks can also allow water to seep into your basement, ruining wood or any stored items.

What Comes With Cracks In Your Concrete Block Foundation?

Usually, cracks are not the only sign something is wrong with your concrete block foundation. There are other strange occurrences you might notice. Such as:

  • Several of your doors and windows could start to stick or not close properly.
  • Your floors could become uneven, bowed, or sunken.
  • Your floors could separate from your walls.
  • Your floors could begin to crack from one wall to another.
  • Your concrete block foundation walls could begin to bow, lean, or sheer. (Sheering means that the top of the wall is moving inward while the bottom of the wall stays put.)
  • Your wallpaper could start to tear and reveal hidden wall cracks.
  • More cracks could form in your home. (Pay attention to diagonal cracks that run from the corners of your doors and windows to the ceiling. If these cracks are larger than 1/10 of an inch, you could have a structural issue.)
  • Your moldings could separate.
  • Your cracks could turn into stair-step cracks which are very dangerous.
  • Your chimney or porch could separate from the rest of your home. (Call an expert to make sure the problem isn’t isolated to the foundation directly underneath your chimney or porch.)

Different Types Of Cracks In Your Concrete Block Foundation

There are two types of cracks that could be in your concrete block foundation: structural and non-structural.

Structural Cracks

A structural crack poses a threat to your home’s structural integrity. Structural cracks could be accompanied by bowing, sheering, or leaning walls. Here’s how you can spot a structural crack.

  • Look for cracks that are wider than 1/10 of an inch.
  • Look for cracks that look like stair-steps in your block walls or brick facia.
  • Look for cracks that run horizontally across your concrete block foundation wall.
  • Look for vertical cracks that run parallel to each other.
  • Look for large diagonal cracks on both sides at the corners of your walls.
  • Look for cracks that run across your ceiling, down towards your walls.
structural vs non-structural cracks foundation pros florida

What Causes Structural Cracks?

Structural cracks are usually caused by differential settlement, expansive soil, hydrostatic pressure, frost-heaving, and lateral pressure.

  • Differential settlement – This is when sections of your foundation settle at different rates. Usually, your home will slightly settle after it’s first built in a process called uniform settlement. Differential settlement is uneven and can cause your concrete block foundation walls to crack.
  • Expansive soil – This is when the soil outside your foundation wall expands and shrinks based on moisture content. When the soil absorbs water, it grows. Then when the soil dries, it shrinks. This growing-shrinking cycle can exert pressure on your walls and cause them to crack.
  • Hydrostatic pressure – Your foundation wall acts as a barrier against the soil outside your home. If the soil accumulates too much water and you don’t have a proper drainage system to carry it away, it starts to push against your wall. This pressure can cause your concrete block walls to crack and bow. Home’s built in high water tables are most prone to hydrostatic pressure.
  • Frost-heaving – When water freezes, its volume increases by about 9%. When soil freezes, its weight increases. This increase in weight will push against your wall. Then, when the soil thaws, the change in weight and pressure allows the wall to fall back to its original position. This back-and-forth movement can cause your concrete block walls to crack.
  • Lateral pressure – If a heavy object, such as a bulldozer or truck, is parked alongside your home, it can cause your concrete block walls to crack.

Non-structural Cracks

A non-structural crack is a crack that does not pose a threat to your home’s structural integrity. But, they can still allow water to leak into your basement. So, you’re going to want to repair these as well. Here’s how you can tell if a crack is non-structural.

  • Look for cracks smaller than 1/10 of an inch. (Anything bigger is structural.)
  • Look for isolated vertical cracks that run from the top of your concrete block foundation wall down to the bottom.
  • Look for cracks that don’t change in size.
  • Look for cracks found in a single block of concrete or brick.
  • Look for thin cracks near windows, corners of walls, floors, below I-beams, or at longer sections of your foundation wall.

What Causes Non-structural Cracks?

Non-structural cracks can be caused by two things: aging and concrete shrinkage.

  • Concrete shrinkage – This is when concrete dries too quickly, causing it to shrink and form hairline cracks.
  • Aging – Over time, concrete block foundations can form thin cracks simply because of time. These cracks are usually smaller than 1/10 of an inch.

How To Repair Cracks In Your Concrete Block Foundation

Foundation Professionals Of Florida are experts at repairing cracks in concrete block foundations. For structural cracks, we use underpinning solutions such as push or helical piers. If bowing walls are causing cracks to form, we use wall plate anchors, helical tieback anchors, c-channel anchors, or carbon fiber straps. If the cracks are non-structural, we can use an epoxy injection to seal them. Injections help waterproof and reinforce your foundation wall.
Read more about wall anchors systems and how they assist foundation repair.

Who To Call For Repairing Cracks In Your Concrete Block Foundation

Call Foundation Professionals of Florida today! We’re an award-winning and top-performing company servicing Florida, Georgia, Alabama, Mississippi, Louisiana, Tennessee, Kentucky, North Carolina, South Carolina, Virgin Islands, and the Florida Keys. Besides foundation repair, we provide basement waterproofing, crawl space repair, slab lifting, and more. Schedule an appointment now!