When Should You Worry About Cracks In Your Foundation?

Originally posted 5/7/20; updated 1/14/22

The health of your home begins at the foundation.  Your house-  and everything in it-  literally depends on the stability of your foundation.   If you’re alarmed when you find a foundation issue like this, you have a good reason to be! 

Your foundation should have regular check-ups just like you do.  Even if you’re not having any symptoms, it’s smart to do a little preventative maintenance.  We recommend that you review your home’s foundation twice a year, using our DIY Home Inspection Checklist.  Seasonal changes can have a significant impact, and catching a problem early is always best for you and your wallet.

Acculevel has been repairing foundations since 1996, and our customers often ask us to diagnose the issues they have found.  In this article, we’ll review the most common types of cracks, and how to gauge the seriousness of the issues they represent.

A Word Of Caution

Please do not try to make foundation repairs yourself.  We understand your desire to be self-sufficient and save yourself some money.  But your home’s foundation is not a good place for DIY experimentation.  Repairing a crack in your foundation isn’t like caulking the edge of a bathtub.  These cracks take different materials and methods, and most of these are not widely available to consumers. 

When done poorly, crack repairs lead to more cracks forming.   And if the wrong diagnosis is made and the wrong method is used? You could actually turn a basic structural crack into a serious structural problem. 

So please, don’t DIY foundation repairs; leave that to a qualified foundation repair contractor.  To help ease your mind, we’ve scored each section for urgency, to help you determine how rapidly you need to act.  The scale we used is 1-5; 1 is the least urgent and 5 being the most critical.

Hairline Cracks In Your Foundation 

One of the most common cracks you will find is a hairline crack.  This type of crack is usually only visible from the inside of your foundation.  

How Do Hairline Cracks Develop?

Seasonal temperature changes create these cracks through the expansion and contraction in your foundation walls.  Concrete isn’t flexible, so when it shifts between wet and dry seasons, it cracks.  These cracks are approximately the width of a single hair, which is what led to their quirky name.  Hairline cracks may (or may not) allow water to seep into your basement or crawl space.

This photo was taken by an Acculevel project advisor during a free in-home assessment.  This crack was discovered when the homeowner removed wet drywall.

Hairline cracks will be super thin, consistent in width, and may let in water.   If you’re unsure if the crack in your foundation wall is thin enough, you can do the penny test.  While holding a copper penny between your finger and thumb, press the edge of it against the crack.  If the crack is thinner than the penny, it qualifies.

These cracks should be repaired before they begin to widen and allow water to seep into your basement or crawl space (if they don’t already!).  This goes back to our message about preventative maintenance; fixing it now will be faster, easier, and cheaper than more serious structural problems.  

At Acculevel, we recommend fixing thin cracks with an epoxy fill.  We have tested a variety of other methods, and this repair type is the one that best meets our requirements.  (We warranty crack repairs for 5 years.)  This epoxy material is only semi-rigid, which means it can flex with the foundation walls and still maintain its seal.

Urgency Score 1: should be repaired within 3-6 months.

Multiple or Wider Cracks In Your Foundation

Have you seen cracks on the outside of your foundation?  Have you also seen cracks in your home’s ceilings, or around door frames? These can be indicators of foundation movement.   

Additional signs to look for if you think the foundation is settling: 

Inside the house: check for cracks in the drywall.  Settling cracks can appear in the walls or ceiling. They are most commonly found around door frames and windows.  If you find any, test the nearest door or window.  

• Does it open and close easily?  
• Will it stay open without you holding it?  
• Does it stay closed without being locked?  

If any of those answers are “no,” then this is more evidence of foundation settlement.

Outside the house: watch for visible cracks in the foundation.  

• Block foundations may have gaps or uneven spacing between the blocks.  This is also true of brick foundations, or block foundations with a brick facade; the cracks follow the mortar joints.
• Stair-step or zig-zag cracks on the outside of your foundation are also possible.

This  photo was taken by an Acculevel project advisor during a free estimate. The gaps and stair-step crack are signs of settling.

Settling is of significant concern.  This is often caused by erosion, or poorly compacted soil under your home.  Foundation settling will only get worse over time, as the soil movement continues.  Stabilizing your foundation will be more difficult and expensive to repair the longer you ignore it.  For repair solutions, please check out our blog on how to repair a sinking or settling foundation.  

Urgency Score 3: should be repaired within 3 months.

If you have drywall cracks and a gap between the baseboard and floor, that may be a sagging floor instead.  We have details about those symptoms in this blog. 

Certain Types of Cracks Indicate Foundation Damage

Earlier, we suggested using our DIY foundation inspection checklist.  One of the things homeowners should be mindful of is structural foundation cracks.

Horizontal Cracks or Stair-Step Cracks

While you’re under your house in a basement or crawlspace, you’re looking for any cracks or signs of damage.  If you find a long horizontal crack with any leaning or bowing walls, you are in dangerous territory.  If your foundation walls are made of concrete block, the cracks may be in a stair-step pattern. 

This photo was taken by an Acculevel project advisor during a routine free estimate appointment. Both horizontal and stair-step cracks are visible here.

As you can see in the picture above, horizontal cracks can appear in any foundation type.  Stair-step cracks are specific to block and brick because they follow the mortar joints.  

Both types of foundation cracks are signs that your foundation wall is losing its battle with hydrostatic pressure.  When the soil outside your home is saturated with water, it applies pressure to the wall (this is known as hydrostatic pressure).  This is a serious threat to your home’s stability, and at this point, you should be alarmed.  

There are several repair options for a cracked or bowing wall, depending on how significantly the wall has moved.  If the wall is only badly cracked or bowing less than 2 inches inward, carbon fiber straps are an excellent repair method.

If the wall is leaning inward more than that, wall anchors or helical tiebacks are a more secure solution.  In either case, please keep in mind that the best answer to hydrostatic pressure is to install water drainage.  This will alleviate the additional pressure and protect your foundation from the stresses of a heavy rain.

Urgency Score 5: should be repaired within the next 8 weeks.

Additional Resources for Homeowners with Foundation Problems 

Not sure how to hire a contractor, or what to ask?  We have additional resources available to you:

• A detailed checklist of questions you should ask a contractor
• 3 steps to getting the best price for home repairs
• Advice on how to safely meet with contractors under difficult circumstances (like the COVID-19 outbreak)
• Our comprehensive foundation guide, which covers everything from crack assessment to settling repairs. 

Do You Have Foundation Cracks that Need Repair?

You need to find an experienced contractor or company that specializes in foundation issues.  We have nothing against general contractors; they are often highly knowledgeable about a wide range of repair methods.  But you need to work with an expert in this field, especially if you suspect a more severe foundation problem.  

Before you sign a contract for any service, you should always verify the company is reputable, insured, and accredited by the Better Business Bureau.   If you live in Indiana or the surrounding states, contact Acculevel.  Established in 1996, we have helped more than 35,000 homeowners restore strength and stability to their homes. We will treat your house as if it were our own.