Wall Cracks 101

A wall crack seems like something pretty simple - throw some spackle on it and you’re good, right? Not so fast.

There are many different causes of wall cracks, and everything from the direction to the placement of the crack can indicate a different cause. And it’s virtually never as simple as throwing some spackle on it.

Let’s go over the kinds of wall cracks you may see in your foundation, and what they mean.

Vertical

Vertical wall cracks *can* be a common side effect of concrete shrinking as it cures. I want to emphasize “can” here, because even though curing cracks aren’t always something to worry about, it’s important to keep an eye on them. If you notice them widening, or they get to the point that you can fit a dime in the crack, it’s time to call us.

Outside of concrete curing, the major cause of vertical wall cracks is foundation settlement. Cracks can appear on the foundation walls as well as the walls of the house as everything else sinks to meet the foundation. When the foundation has settled enough that the affected corner of the house begins to rotate outward, you’ll see a vertical crack that’s wider at the top than the bottom.

Regardless of their cause, vertical cracks can allow a large influx of water, which will not only get your basement wet, but can further widen the crack, creating a vicious cycle.

Horizontal

Horizontal wall cracks are often accompanied by bowing in the wall, and are caused by soil movement that puts pressure on the foundation wall. As pressure from the soil continues, the wall will bow further and the crack will widen.

Soil shift can be due to soil composition (e.g. silt) or even come from severe weather shifts. For example, when the ground freezes it contracts, but it expands upon thawing. If it expands beyond its former space (due to heavy saturation), it can push into the walls.

A wall can only bow so far before gravity takes over, so it’s important to get the problem taken care of as soon as you notice a horizontal crack. Wall failure isn’t out of the question in situations like this.

Stair Step

The stair step crack sounds (and looks) like a unique situation, but it all has to do with the composition of the foundation wall. Stair step cracks form in block walls (as opposed to poured concrete). As the wall crack begins to form - regardless of the cause - it can travel along the mortar joints between individual blocks, forming the stair step appearance.

Stair step cracks are indicative of foundation issues, be they settlement or bowed walls, and need to be addressed promptly. Water influx can degrade the mortar between blocks and threaten the integrity of the wall; this is another situation where complete wall failure is possible.

Solutions

For cracks that aren’t caused by foundation issues, sealing is still necessary. Our FlexiSpan system creates a watertight seal that moves with the wall as temperature fluctuations cause it to shift, preventing future leaks.

For vertical cracks and foundation settling, our piering system can stabilize your foundation by shifting the weight of the foundation from the soil to the pier, which is drilled down to a depth that prevents further shifting. Piering can also be used to stabilize garages and retaining walls - not just homes.

Horizontal and stair step cracks caused by bowing walls can be stabilized by one of our wall reinforcement products. PowerBraces span the wall all the way from the footer up to the joists, and Wall Anchors are, you guessed it, anchored into the soil a distance away from the house. Both can be tightened over time, which can lead to straightening the wall in addition to stabilizing and reinforcing it.

Regardless of what’s causing the cracks in your walls, it’s important to have an expert look at them. Luckily, we’re experts! Call us and we’ll design a solution to keep your home dry and safe.