Foundation Inspection Procedures

The individual type of crack and even just the size of the crack shouldn’t necessarily be the only thing you pay attention to. You should also consider additional factors, like the building’s history, soil, materials used for construction, and other external factors.

How significant is a specific foundation crack? Here are a few examples of different foundation crack severity. 

• Minor Foundation Cracks

The biggest thing that puts a crack into the “minor” category is when it is relatively small. Here are a few examples of common minor foundation cracks.

• Horizontal hairline cracks less than one-sixteenth of an inch wide
• Any concrete slab cracks less than one-eighth of an inch wide that don’t extend into the foundation
• Stair step or vertical cracks less than one-eighth of an inch wide that don’t extend into the foundation

These cracks are what most people would call “cosmetic.” They typically don’t require repair, but you’ll still want to be diligent in your wall crack inspection to make sure you don’t see any other structural concerns.

• Moderate Foundation Damage That Requires Monitoring or Repair

These are more common foundation damages. They can indicate a small amount of structural damage, but for the most part, they don’t indicate a serious foundational concern. Here are a few examples of moderate foundation cracks.

• Old cracks with no sign of continuing widening or movement
• Mortar cracks caused by backfill being installed too early
• Horizontal bulges less than an inch and a half with no other sign of foundation cracking or damage

You may be able to save the homeowner money if you fix these problems early on. For example, horizontal bulges can easily turn into significant basement wall bowing, so it’s a good idea to handle it when you see it. However, these aren’t significant enough to be potentially hazardous right now.

• Severe Foundation Damage That Requires Immediate Professional Inspection

There are some types of foundation damage that are so significant they can indicate potentially deadly signs of failure. If you see any of these examples of severe foundation cracks, consult a foundation repair expert immediately.

• Sudden and severe foundation cracking, especially in areas prone to sinkholes
• Bulges or basement wall bowing 1.5 inches or more
• Leaning walls or lateral dislocation .25 inches or more
• Signs of recent or recurrent movement and settlement
• Any cracks wider than three-eighths of an inch

These signs of foundation damage can mean that the home you’re inspecting has a very serious foundation problem. If you see any of them, talk to a JES expert as soon as possible.

The first thing to know is that there are many different types of foundation cracks. These cracks all have different problems associated with them and therefore different methods of repair. Along with having the knowledge of the types of foundation cracks you should also know how their significance may change due to different factors.

These are some of the different types of foundation cracks you may run into, as well as a description of how to deal with them in different situations. 

• Hairline

Of all different types of cracks, hairline cracks are usually the cracks that cause the least potential for problems. Hairline cracks are typically less than one-sixteenth of an inch wide and aren’t uniform or connected to each other.

For the most part, hairline cracks are just cosmetic and don’t present a structural problem. You may want to look for the actual reason why; most commonly, it’s due to concrete shrinkage, which isn’t necessarily a problem. However, if it’s due to spalling or improperly placed steel reinforcement, you need to address it immediately. 

• Uniform

Usually, uniform cracks also aren’t a significant problem. These problems may also occur due to shrinkage. As long as you find them near the center of the concrete, rather than at the edges or extending to the bottom, they usually don’t showcase a serious issue.

When it comes to uniform cracks, one thing you should notice is how wide they are. Cracks that are wider than one-sixteenth of an inch but narrower than an eighth of an inch are unlikely to showcase a structural problem. 

• V-Shaped

What if the crack is wider at one end than the other? These are “V-shaped” cracks, and they may be important to pay attention to.

The first thing to determine is which side is wider. Is it wider at the top of the crack or the bottom? Cracks that are wider at the bottom tend to showcase more of a structural problem than those that are wider at the top, especially if they’re in a concrete block wall or a brick wall.

Another thing to notice is the placement of the crack. If the crack is V-shaped, wider at the top, and doesn’t extend to or past the bottom of the foundation wall, it’s likely to be a shrinkage problem. Contrast that to a crack that is V-shaped, wider at the top, but extends past the bottom of the foundation wall, which is more likely to be structural.

Additionally, a V-shaped crack that’s in the corner to an adjacent opening could showcase structural problems. Pay close attention to the wall adjacent to the opening, because even an otherwise safe crack can mean the area’s experiencing structural issues. 

• Broken Bond Courses, Bowing

You may see these cracks in brick foundation walls. The concept of “broken bond courses” happens when the grouting between bricks starts to crack.

These cracks typically happen either at the same time or just before you start to see bowing in the basement walls. If the basement wall is bowing one inch or further, you need to treat it as a serious problem. It can happen because of settlement, movement or thermal expansion, and can result in problems as serious as collapse.

Broken bond courses can also make other types of cracks more serious. For example, even a V-shaped crack that’s wider at the top and doesn’t extend past the bottom of a foundation wall can showcase serious problems if it’s in the brick bond. 

• Stair-Step

It’s most common to see stair-step cracks in brick walls because it’s typically the easiest way for brick to crack. However, you may also see it in concrete block foundations. These cracks typically happen because the foundation is settling further to one side than another.

Although this doesn’t inherently mean that a foundation is on the brink of collapse, it does mean you need to pay attention to other signs of house settling. If pieces of the brick bond are falling out or the bricks appear to be rotating out, you should also look for other structural issues. 

• Horizontal

There are many types of horizontal cracks out there. Horizontal cracks can mean a variety of things for the home’s foundation, but one of the things it most commonly means is that the wall is on the brink of bowing.

One thing you should pay attention to is where on the wall the crack is. If it’s low, near the bottom, it can be a sign of early foundation failure, and it probably indicates that the home requires additional foundation support. Mid-height often indicates wall bowing, and you may find water if the crack was caused because of hydrostatic pressure. Horizontal cracks in the upper third of the wall often indicate frost damage. 

• Vertical

Vertical or diagonal cracks tend to indicate structural concerns. This is especially true if you see very significant cracks, but some areas may indicate structural problems even if they’re otherwise pretty small.

An especially important concern comes if you’re seeing vertical or diagonal cracks at the center of the header or the corners of the building. This can be seen in brick or concrete foundations. These can be some of the worst cracks because they typically indicate foundation failure, and you should pay attention to them immediately.

Another type of vertical crack to note is one that happens underneath a ground-level window. If the crack reaches from the window all the way to the ground, it could indicate structural problems, especially in the initial construction of the window.

Foundation crack inspection is an important part of your inspection, but cracks aren’t the only things you should be paying attention to. You also need to pay attention to other problems that could be showcasing serious foundation failure.

As you do your home inspection, keep an eye out for these additional measures of foundation failure. 

• Dislocated Wiring, Plumbing, or Lines

Not only can these be a safety concern all by themselves, but they can also showcase serious foundation failure. That’s because dislocated wiring, plumbing and lines typically only happen if the structure is experiencing very serious settlement or movement. Keep an eye out for these and verify with the homeowner that there hasn’t been any external force that could have dislocated these lines. 

• Broken Structural Connections

It’s very important that the structure stays on top of the foundation. However, if you notice the structure has shifted off that foundation, that means there are serious foundation problems of some kind inside it. If you see a shifting structure on top of the foundation or slab, or you discover broken sill bolts, it’s a good idea to consult a JES foundation repair expert for your next steps.

• Bowed Walls

Bowing of any kind is an important thing to pay attention to. Bulges, which are an isolated section of the wall that pushes out, can be a moderate foundation concern if it’s less than an inch and a half. However, if you see the wall bowing outward, it means there’s too much pressure on the inside. It’s important to talk to a JES expert to discover the source of that pressure and see if you can relieve it. 

• Leaning Walls

In some cases, you might see the walls leaning slightly inward or outward. Any leaning is important to tackle as soon as possible because it means there’s some form of structural damage. However, it’s especially vital that you start structural repairs if the lean is more than a quarter of an inch. A JES expert can help you learn more about how to fix it.

• Wall Leaks

One vitally important thing to pay attention to is any foundation cracks that allow water into the crawl space or basement. Water loves to get into places where it shouldn’t be, and that includes crawl spaces and foundations. If you’re seeing water leaking into a basement, it’s going to cause all sorts of problems, potentially including structural concern down the line.