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Foundation Cracks – Understanding Good & Bad Foundation Cracks

While some foundation cracks in the home are harmless, diagonal, horizontal, and stair-step cracks pose serious risks and should be fixed promptly.

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All homeowners, at some point, deal with foundation cracks. It is one of the most nerve-racking experiences. What most people don’t know is that some foundation cracks are quite harmless. Others are so bad they can cause the whole house to collapse. The key to safeguarding your home is to understand the types of cracks on your foundation and get a proper fix before it’s too late.

Still not sure if your foundation cracks are good or bad? Get an expert opinion today to avoid expensive repairs in the future.

Are there good foundation cracks?

Foundation cracks appear in both new and old homes all the time. Any house that is built with concrete will have a few cracks. This is a common thing in poured concrete foundations. The general rule of thumb with any crack is this: if it’s small, it isn’t that bad. Good cracks indicate a building that has settled in its foundation, or the concrete has completely cured.

Vertical cracks are the most common type of foundation cracks in a home, especially newly built ones. They’re caused by the tension created when the concrete dries. Another cause is water pressure from rainwater.

Fixing vertical cracks is super easy and inexpensive. It involves injecting an epoxy or polyurethane solution into the cracked foundation. Both of these solutions are lightweight and durable. When applied properly, they will seal your vertical foundation crack permanently.

Foundation cracks that should worry you

Some foundation cracks are a major cause of concern. They’re known as structural cracks. If you see any of these cracks in your house or building, you should get a licensed home inspector or structural engineer to inspect them as soon as possible. By fixing them, you can avert many foundation problems.

Diagonal Cracks

The first type of crack that signifies a problem with your foundation is the diagonal crack. It usually runs at an angle of between 30 and 70 degrees. What differentiates diagonal cracks from vertical cracks is that they generally have one wider end and a narrow or tapering end. Some can run the entire length of the foundation wall.

When these cracks occur, it’s because of differential settlement of the home. This is when some parts of the house settle while the rest remains stable. It’s a common phenomenon in houses built on slopes or uneven foundations.

Just like vertical cracks, these types of cracks can be fixed by an epoxy or polyurethane solution. Diagonal cracks will take more material to fix when you compare them with vertical cracks. You also need to determine where the settlement is taking place to prevent future ones. Foundation piers may need to be installed by a professional contractor depending on how much settlement and damage has occurred.

Horizontal Cracks

You will mostly find these in basement walls. When they occur, it could be a sign of serious structural problems in your building. Horizontal foundation cracks are worse than diagonal ones and complex to repair. Most of them are wider than 3 mm.

Cracks of this type occur when the ground pressure exceeds the strength of the basement walls, causing the wall to bow inwards and to crack in a horizontal manner. More often than not, they can be attributed to the use of heavy equipment around the building or excessive backfilling. Frost heave can also cause horizontal cracks in block or concrete foundations.

Horizontal walls pose serious structural risks. In the worst-case scenario, they can cause the whole building to collapse. The moment you notice them in your basement, you should call a qualified home inspector or structural engineer to assess the extent of the damage. You will be told whether you’re going to repair or replace the foundation.

Fixing the horizontal cracks may involve a number of things including removing the excessive backfilling, installing supports, and redoing the entire foundation wall. Repairs will depend on the severity of the damage and the type of foundation.

Stair-step Cracks

Another severe type of foundation crack you shouldn’t ignore is the stair-step foundation crack. These usually occur in brick or block foundation walls. Cracks appear on the mortar joints of the bricks or blocks. Just like diagonal cracks, they’re caused by soil settlement. This happens when the foundation of the house and the soil under it move horizontally and vertically.

Fixing stair-step cracks involves re-pointing the walls if the damage is not severe. Where necessary, piers may be installed around the foundation of the house to prevent further settlement. Only a licensed

structural engineer or home inspector can determine the extent of the damage and settlement to determine your next course of action. Timely repairs can prevent a potential disaster.

Don’t let foundation cracks cause you sleepless nights. Schedule a free inspection and estimate with the expert team at Mount Valley Foundation Services and get a lasting solution to your problem.

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