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How To Repair a Foundation

Foundation repair isn't easy or cheap, so it’s vital to take care of your foundation and work with experienced professionals. Learn more here.

January 1, 2018

Foundation repairs are every homeowner’s nightmare. However, it doesn’t have to be all doom and gloom. Foundation repairs are possible when you work with experienced professionals. Furthermore, there are things you can do to protect and preserve your foundation to prevent issues from developing down the road.

So if you do need foundation repairs, don’t fret—Cottage has some resources here to help guide you through it.

What Is a Foundation?

Simply put, a foundation is the foundation of your home—meaning that it’s the lowest load-bearing part of the structure. Foundations bear the weight of the entire house and quite literally keep the walls up. Where possible, foundations are built into the ground to provide as much support as possible.

What Are the Different Types of Foundations?

Now that you have an understanding of what a foundation is, it’s time to review a few of the many types of foundations. While there are several different foundations, this section will cover poured concrete foundations, concrete block foundations, and stone foundations.

Poured Concrete Foundations

Poured concrete foundation involves simply pouring concrete over a prepared area to create a foundation. This is the most popular type of foundation used in construction today because it’s very leak-resistant and easy to waterproof.

Concrete Block Foundations

Concrete block foundations involve concrete “bricks” or cinder blocks stacked together and assembled to create a foundation. Concrete block foundations can hold more weight than poured concrete foundations. However, the gaps between each block result in an increased risk of leaks and water infiltration.

Stone Foundations

Stone foundations are commonly found in older homes constructed before the 20th century. Stone foundations are quite similar to concrete block foundations, wherein several layers of dry-stacked stone are assembled to create a foundation.

Why Is a Foundation Important?

The importance of your home’s foundation cannot be understated.

Here’s why your home’s foundation is incredibly important:

  • Support: First of all, the foundation supports your home. If you were to build a house without a foundation, it would simply sink right into the ground.
  • Movement Prevention: Secondly, the foundation prevents movement in your home. With no foundation, you would have cracks and gaps running through your walls, floors, doors, and windows.
  • Insulation: The foundation insulates your home from the outside elements. Not only does this keep you comfortable throughout the different seasons, but it can also save you on energy costs.
  • Moisture Prevention: The foundation prevents moisture from getting into your home and damaging it. Moisture can come from all directions, including from rain, snow, and soil.
  • Insect Protection: Finally, the foundation keeps insects and other pests out of your house that can wreak havoc on your belongings and your sanity.

What Are the Signs of a Bad Foundation?

Although you likely get a home inspection when you initially buy your property, house foundation issues can occur at any time, which is why it’s essential to inspect your home for signs of foundation issues regularly. But what exactly should you be on the lookout for?

Here are some red flags that indicate that you may be dealing with foundation issues:

1. Cracks

Cracks are perhaps one of the biggest signs of foundation issues. Cracked foundations can significantly decrease property value.

That being said, you shouldn’t immediately start panicking if you see a few small cracks here and there. For example, 1/16” hairline cracks are common in walls and floors since the house tends to sink a little bit in the first two to three years after construction.

You do need to be concerned about bigger cracks and cracks that develop several years following construction after the foundation has had plenty of time to settle. Moderate wall and foundation cracks are considered to be between 5 and 15 mm in length and .2” to .6” in width.

Serious cracks are considered to be above 15 mm in length and greater than .6” wide. Be on the lookout for horizontal cracks rather than vertical cracks and cracks that appear at a 45-degree angle.

2. Sinking

Sinking is another sign of potential foundation issues. As you now know, a little bit of sinking or settling is expected in the years following construction, but sinking over time is a sign of a more significant issue.

For example, if you notice that one side of your house is lower than the other side. Specifically, you need to be on the lookout for any signs of sinking, no matter how small.

This is because what may start out as a small ½” dip on one side of your foundation could easily develop into a dip of several inches if you’re not careful and proactive. As a result, it’s crucial to periodically inspect your house, including the foundation. Look for signs of sinking, settling, gaps, and unevenness.

3. Rising

On the other end of the spectrum, a rising foundation indicates foundation issues. Also known as foundation upheaval, this occurs due to things like excessive moisture and the expansion and contracting of soil.

You need to keep a close eye on the perimeter area of your foundation, as this is where rising most commonly occurs. Additionally, it commonly occurs along outside garage walls. If you’re not careful, foundation upheaval in these areas could affect the interior of your home.

4. Door Issues

One sign of foundation problems is when you constantly have problems opening and closing your doors. With interior doors, they tend to stick or drag at the top. With exterior doors, they tend to drag at the threshold or hang down at the top. With double doors, they might look uneven or might not meet in the middle.

It doesn’t take a lot of foundation movement for you to start having issues with your doors. In fact, just ¼” of an inch can result in stuck doors. Note that stuck doors aren’t automatically an indication that you have foundation problems, as this issue could be caused by a whole host of other issues completely unrelated to your foundation.

But if you notice door issues and are concerned, be sure to have someone come check out your foundation for your peace of mind.

5. Window and Door Gaps

Similarly, window and door gaps are signs of potential foundation issues. These gaps most commonly appear with exterior windows and doors. Eventually, you may not be able to close your doors or windows properly.

6. Uneven Floors

In terms of your foundation, you need to be on the lookout for uneven floors—another classic sign of foundation issues. Specifically, sagging, bowing, or dipping floors could indicate trouble. What may start as a minor issue of less than ½” can quickly develop into 2” over the years if unaddressed.

7. Separating Cabinets and Counters

While you might initially assume that separating cabinets and counters is a sign of poor installation rather than a sign of foundation issues, these are more red flags that you should be aware of.

This is because when your walls aren’t level due to foundation damage, the things attached to your walls, including cabinets and countertops, cease to be level. So signs of sloping or separation should be taken seriously rather than ignored.

8. Damp Crawl Space

If your crawl space is really damp, this could also signify that your foundation isn’t working as it should be. As you now know, one of the main functions of a foundation is to keep moisture out. So when it’s not doing that, there has to be an underlying reason.

On a similar note, keep an eye on basement walls. Crooked basement walls can affect the entire home above them.

9. Drainage Issues

Drainage issues in your yard could indicate an issue with your foundation. Drainage issues could be caused by a number of different things. Consult with a professional to determine the cause and evaluate any damage to your foundation.

10. Warped Siding

Warped siding is another issue that may seemingly be caused by poor installation but may actually be a sign of foundation issues. Be on the lookout for siding that’s warped or has gaps or overlaps.

What Are the Causes of a Bad Foundation?

Now that you know the signs of a bad foundation, review some of the causes of a bad foundation.

1. Poor Construction

For starters, poor construction could quickly cause foundation issues. If you’re moving into an existing home, there’s not much you can do about this except to get a good inspection before you close and keep an eye on your foundation after you close.

If you’re building, then it really goes without saying that experienced and reputable contractors are worth their weight in gold since you’re quite literally putting your future in their hands.

This is why Cottage only works with a network of fully qualified, vetted, licensed, and insured contractors for all ADU projects.

2. Soil Composition

Soil composition is often the main cause of foundation issues. Odds are you’ve never even thought about your soil composition before, but as a homeowner, this is something you need to think about. This is because soil sits underneath your foundation and impacts how it behaves. Throughout the year, soil can go through a lot of changes.

For example, it might be too dry in the dry summer months. Alternatively, it might be too wet in the rainy season. Both of these could result in foundation issues if you’re not careful.

3. Temperature Changes

On a similar note, frequent temperature changes could cause foundation issues because soil tends to shrink when frozen before expanding again. Over time, countless instances of shrinkage and expansion could easily result in foundation issues.

4. Water Infiltration

While one of the main purposes of your foundation is to prevent water infiltration, it’s not able to prevent all instances of water infiltration on its own. For instance, a plumbing leak in a pipe below your home could result in serious foundation issues if not addressed quickly.

Another example involves improper drainage around your foundation. When water starts to pool around your foundation during heavy rain, this excess water can easily infiltrate your foundation and cause long-lasting damage.

5. Tree Root Infiltration

Finally, tree root infiltration can wreak havoc on your foundation if you’re not careful. Tree roots are incredibly strong and can cause damage to foundations, driveways, sidewalks, and more. For this reason, it might be a good idea to avoid planting huge trees with strong, complex root systems right next to your house.

How To Repair a Bad Foundation

While foundation issues are never fun, the good news is that it is possible to repair a bad foundation using these methods:

1. Sealants and Masonry Patches

Small cracks in the foundation may be able to be repaired using sealants and masonry patches. Some examples of different types of sealants include hydraulic cement, vinyl concrete, epoxies, silicone, and polyurethane. It’s essential to seal any noticeable cracks as soon as possible to prevent water infiltration that will only exacerbate your foundation issues.

2. SlabJacking

If you have a foundation that’s noticeably sinking or rising, one repair option involves SlabJacking, also known as mudjacking, concrete lifting, and slab leveling. SlabJacking is ideal for addressing unevenness in small areas like porches, driveways, and garages.

In this method, holes are drilled through the concrete slab to access the space below. Then, grout is injected through the hole into the void that started all this trouble in the first place. Common materials include sand, gravel, ash, and more (often all mixed together).

3. Piering/Piling

For a more long-term solution or for a more extensive project, you could use piering or piling to repair your foundation. There are several different types of piers and pilings available, depending on the construction of your home and the severity of the issue.

For example, there are pressed concrete pilings, poured concrete piers, belled concrete piers, steel piers, and helical steel piers. These piers and pilings are driven deep into the soil to provide additional support to a failing foundation.

4. Soil Modification

Since soil can be an underlying cause of foundation issues, it often makes sense to address the root cause when dealing with foundation issues. Soil amendments are added to the soil to strengthen it to the point where it can adequately support your foundation.

Can You Repair a Foundation Yourself?

While it may be tempting to test out your DIY skills on your foundation repair, this might not be the best approach. Keep in mind that the foundation is the most vital element of your home. As a result, it’s definitely worth investing in an experienced professional so that your home is adequately protected.

How Much Does Foundation Repair Cost?

Professional foundation repair may not be cheap, but it’s worth it.

Just how much does it cost? It all depends on the extent of your foundation damage and the ideal foundation repair method. For example, minor home repairs using sealants and masonry patches will be less expensive than major repairs using piers or pilings.

Repairing minor cracks using patching can cost as little as $500, while major structural repairs can cost as much as $10,000. On average, the cost of foundation repair is about $4,000, with a range between $1,800 and $6,500.

Keep in mind that whatever you spend on foundation repair is an investment in your most valuable asset: your home.

How To Protect and Preserve Your Foundation

Since foundation repair is incredibly critical and costly, take steps to protect and preserve your foundation; be proactive rather than reactive. While you may not be able to 100% prevent foundation issues in all cases, there are things you can do to help protect and preserve your foundation the best you can.

Make sure to:

  • Regular Inspections: Inspecting your house once before you buy it is not enough. You need to be inspecting your home for signs of foundation issues regularly so that you can catch things early. Early detection of structural integrity will save money in the long run.
  • Invest in Drainage: While it may not be particularly exciting to invest in proper drainage for your home when you’d rather spend that money on a new kitchen, investing in drainage now to protect your foundation can save you time and money later.
  • Proper Landscaping: Landscaping is another interesting way that you can protect and preserve your foundation. Avoid planting things right up along your foundation, as plants can soak up much-needed moisture from your foundation and prevent proper air circulation. Additionally, roots can cause extensive damage to your foundation.

Home Improvement and Foundation Repair

Foundation repair—while complicated and expensive—can be avoided in many cases. This is especially true when you’re building from scratch. When you work with professional ADU builders like Cottage, you can rest assured that your foundation is laid properly. In fact, all of Cottage’s work comes with a one-year workmanship guarantee.

All of Cottage’s predesigned ADU floor plans come with best practices modern foundation design built in. To find out more, reach out to an expert to get started with a customized ADU project today.


Is a Poured Foundation Better Than a Concrete Block One? | The Washington Post

How to Find a Reliable Home Contractor | Real Estate | US News

Your Step-By-Step Guide to Inspecting Your Home | Forbes

Repairing a Sinking Home Foundation With Slab Jacking | The Spruce

Techniques of soil modification for re-use in construction | IOPscience