Even the most solid house construction will develop cracks at some point in time. But there are different types and sizes of cracks, and some are more concerning than others.
Basement cracks can be tough to diagnose. Warning signs may initially be slight—the kind where you shake your head and think that maybe you’re imagining that musty odour or increasing humidity.
In this post, we teach you what you need to know about how to diagnose and fix a crack in your basement wall.
Types of Basement Wall Cracks
The first thing you need to know is that your basement walls can develop different types of cracks.
You may have just one type of crack in your basement wall or you may have all different types of cracks. Which types of cracks you'll see depends on the types of pressures your basement is experiencing and how it is constructed.
The basic types of cracks are horizontal, vertical, diagonal and stair-step.
Horizontal cracks are commonly caused by the natural shrinkage of drying concrete. These cracks can be the toughest to spot because they are often quite tiny!
The biggest risk with horizontal cracks is moisture seepage. Because they can be so difficult to spot, it is important to know other warning signs to look for. Increasing humidity, a grassy or musty odour, allergy symptoms, and formation of mildew or mould are the most common warning signs.
Vertical cracks are commonly caused when a basement wall begins to bow during or after construction. There are many reasons a wall may bow inward, including pressure from surrounding earth, especially if the crack is midway up the wall where pressure is greatest.
These cracks are typically easier to spot—they tend to be larger and will continue to spread over time. The biggest risk with vertical cracks is structural damage to your home.
Diagonal cracks can develop in several ways. Sometimes the crack will be wider at the top and narrower at the bottom. The reverse is also possible. Diagonal cracks can also develop around structures like windows and doors. If your basement is missing anchor bolts or the surrounding earth is causing pressure, these cracks may start to appear.
These cracks are typically pretty easy to spot except when they form around windows or doors and are quite small or hidden by door jambs or window sills. The biggest risk with diagonal cracks is that the structural integrity of your basement can decrease.
Stair-step cracks form for similar reasons as for diagonal cracks. But these types of cracks will only form in basements constructed using concrete blocks rather than poured concrete. As their name suggests, stair-step cracks follow the structure of the blocks, leading to a "stair-step" crack pattern.
The biggest risk with these types of cracks is, again, the structural integrity of the basement being compromised.
What to Do If You Suspect Basement Cracks
Home ownership comes with an ongoing steep learning curve. Most of us don't go into home ownership knowing exactly what steps to take when our basement wall develops a crack.
So there can be a very natural moment of panic followed by lots of questions! This is quite normal and we get these types of calls every day.
Whenever you suspect or visibly see cracks forming in your basement walls, the first step is always to do more research. You want to find out what is causing the crack. You also want to know if there are other cracks. And you want to know whether the cracks you are seeing are the type where a "watch and wait" approach is recommended or if you need to take action right now.
Have a professional come out and do this research and make a diagnosis. This way you are not wondering and worrying. You know what you are dealing with and what your options are, and you can make practical decisions.
How to Fix a Crack in Your Basement Wall
You now know that there are several types of basement cracks that can form. Some may form right away due to the natural process of drying concrete. Others may form later due to structural changes in the earth surrounding your basement. Still others may form for other reasons relating to how well your basement was constructed or the types of materials used.
The good news here is that regardless of the types of cracks you are seeing or how mild or severe they may be, they absolutely can be fixed!
The most common fixes we recommend include these:
Providing more support to your basement walls is always a good idea when there are changes due to the surrounding earth. For this reason, we often recommend installation of additional wall anchors to prevent further movement of basement walls due to outside pressures.
Basement waterproofing is the most effective tool we have found to fix cracks that may not be causing severe structural concerns but nevertheless present their own significant risks if left unaddressed.
For example, basement waterproofing can be a particularly important step to take if you have the types of hairline cracks that are permitting moisture to seep in. This can lead to mildew and mould that will literally rot your home from the inside out.
These fixes are sometimes recommended in tandem when your basement structure has developed multiple types of wall cracks.
Get in Touch
Contact us online or give us a call at 1-866-875-6664 if you suspect your basement may have a crack!