Foundation Cracks – Understanding Good & Bad Foundation Cracks

Friday, December 20th, 2019

Any person who values their home will naturally be alarmed to see cracks in their foundation walls. Concrete foundations are prone to cracks. The question is not if they will crack, but when. With that in mind, you should always be on the lookout for foundation cracks. They may start small like hairline cracks and widen with time, letting in water and insects.

Cosmetic Cracks Are Not Dangerous

Most cracks are cosmetic. While unsightly, hairline cracking is a normal thing in most North Carolina homes. They don’t usually indicate serious structural risks or create unsafe conditions. Such cracks are usually narrow and occur at offset corners. If you notice a crack that’s hairline to about 1/8 inch in width, don’t worry about it. Epoxy injection is all you need to fix it.

However, if you have repaired these cracks and they’re back within a short time, it’s a clear sign your foundation is on the move. Ask a structural engineer to examine your foundation.

Structural Cracks Pose Serious Risks

Any crack that’s in the range of 9/16th to 1 inch should be a real cause of concern to any homeowner. They could signal a deeper and larger problem. Because they’re wide, such cracks easily let in water, insects, pests and radon gas. Moisture causes mold problems while radon is a toxic gas. Insects and pests can infest your basement, climb up to the living area, and cause all kinds of problems from contamination to structural damage.

Telltale signs of structural cracks include:

• Diagonal cracks at corners of concrete foundation walls (poured)
• Horizontal cracks or stair-step cracks along foundation walls
• Bulging and inward bowing of walls
• Walls leaning inwards at the top
• Inward sliding of walls at the bottom
• Moist clay around the home

All these signs indicate the soil beneath the foundation is moving and your foundation is moving. In case you notice any of these, contact your local basement and foundation repair contractor to avert more foundation problems.

Pay attention to the size, direction, shape and the location of cracks. Depending on the nature or depth or seriousness of the crack, your contractor may install foundation piers, use carbon fiber reinforcement, or do concrete lifting to raise and restore sunken concrete slabs. All these require the input of a skilled and licensed professional.

What Causes Foundations to Crack?

When the foundation cracks, it’s normal to want to know what instigated the gaps. Several things can cause cracking, and the most common culprits are:

1. Contraction of concrete: As concrete slabs harden, they lose moisture. Evaporation causes them to contract and shrink. The concrete may put on some resistance for a while but it will eventually give in to the tension that pulls it apart, resulting in cracks.
2. Foundation settlement: It’s normal for the foundation of a new home to sink two or three years after construction because of its weight. The downward movement isn’t always even, resulting in cracks. After that, the foundation will stabilize. Foundation settlement repair can rectify the problem.
3. Poor construction: Before a new home is built, the soil should be tested and compacted, then the appropriate footing designed to support the home. Some builders overlook these steps or skip them. Still others use substandard materials, causing your foundation to crack.
4. Tree roots: This may come as a surprise. Roots of big trees are pretty strong. When they make their way into the soil beneath the home, they can lift sections of the foundation, causing it to crack. Make sure you don’t plant them near your home.
5. Dry soil conditions: During dry weather, the soil under the foundation tends to shrink. This creates a significant gap between your home’s foundation and the surrounding soil. Back and forth pressure on the foundation causes it to shift and fill the gap.
6. Hydrostatic pressure: After a heavy downpour, the soil around the perimeter becomes saturated and heavy. This exerts inward pressure on the foundation walls, causing it to bulge and crack.

Whether you’re dealing with hairline cracks or more structurally severe cracks, it pays to have foundation repair contractors in North Carolina inspect your basement and foundation walls. Though they may not guarantee you the cracks are harmless, they know how to tell a bad crack from a good one and how it should be repaired.

Have foundation cracks in your home or burning questions on the same? Contact your local contractor to get answers by scheduling an appointment for a free foundation inspection and repair estimate today.