Hearing the words “your foundation has heaved” can stop you in your tracks. You might be thinking, “Wait, I thought foundations only settled downward, what’s this about going up?!” It’s confusing, concerning, and definitely not something you planned on dealing with as a homeowner.
Full disclosure time–heave isn’t something we’ve seen much of in 40+ years of fixing Brazos Valley foundations. Settlement is much more common. But we have seen it a handful of times, and when it happens, it’s very obvious. The good news? The cause is usually clear and can be dealt with once you know what’s going on.
To help you tackle this issue confidently, this article will break down what foundation heave is, why it happens, and what you can do to get it under control so you don’t end up throwing money at the wrong fix.
What Is Foundation Heave?
Foundation heaving is the upward movement of a home’s foundation (typically slab foundations, but it could affect crawl space homes as well) caused by expansive soils swelling up when they soak in too much water. Think of it as the opposite of settlement. Instead of your home sinking down, part of it gets pushed up.
An easy way to picture what expansive clay soil does is to imagine a dry kitchen sponge. When you pour water on it, the sponge swells and gets thicker. Clay soils under your home behave the same way–they expand when soaked, and if one spot swells more than the others, it can lift part of your home.
This uneven push can leave you with all kinds of confusing signs like doors sticking, walls cracking, or floors sloping. It may feel like your home is misbehaving for no reason, it may even look a lot like foundation settlement, but there’s always an identifiable source behind foundation heave.
What Caused This Foundation Heave?
Heave can come from several different sources. Most of them are related to excess water getting into the soils under your slab. Sometimes it’s how the home was built, and sometimes it’s just Mother Nature doing her thing. Here are the usual suspects:
Water / Moisture Related Causes:
- Broken drain line under your slab
- Leaking water supply line
- Periods of excessive rain
- Poor drainage around your home (yard sloping toward the foundation, missing or broken gutters)
Construction-Related Causes:
- Building on a cut slope without letting the soil adjust
- Improper pad site preparation or inconsistent soil compaction
- Constructing during a very dry season followed by a heavy rain season
Other Causes:
- Removing a large tree near the foundation that used to soak up a lot of water
- Good old-fashioned expansive clay soils behaving as expected
- Prolonged flooding event
How Do I Fix Foundation Heave?
The first step in fixing the heave issue is to address any present moisture problem. If water is the culprit, the area needs a good chance to dry out. This could mean repairing a plumbing leak, fixing your drainage, or improving guttering.
Here’s the catch: while heave can happen quickly, the drying-out process takes time . . . sometimes many months. The soil needs to shrink back down, and that doesn’t happen overnight. Think about a soaking wet mattress out in the sun, it might dry eventually, but it ain’t happenin’ real quick. The soil under your slab works the same way.
Bonus Tip: Just because one part of your home is higher doesn’t mean you should raise the rest of the house to match either. That would be an extremely expensive project (and we don’t ever recommend it) and almost certainly lead to plumbing nightmares under your slab.
Make sure any contractor evaluating your home knows the difference between settlement (downward movement) and heave (upward movement). You don’t want the wrong fix for the wrong problem.
Foundation Heaving FAQs
Well, now you’ve found that you have a few MORE questions about heaving homes. Here’s some of the common follow up questions homeowners ask during a heave-y discussion:
How Do I Know If I Have Heave or Settlement?
Settlement means your foundation is sinking down, while heave means part of it is being pushed up. Signs like doors sticking, cracks in walls, or uneven floors can show up in both heave and settlement situations, so you’ll likely need a professional to tell the difference.
How Long Does It Take for Foundation Heave To Go Away?
It depends on how much water is involved and how fast the soil can dry out. Heave can happen in weeks, but it may take months or even longer for the soil to shrink back down and your home to eventually respond. Hey, at least you’ve got gravity on your side to possibly help move things along . . .
Can Foundation Heave Be Prevented?
Good drainage is your best defense. Keep gutters clean, slope your yard away from your foundation, and fix plumbing leaks quickly. You can’t prevent every situation, but you can lower the risks.
If It’s Not Heave, It Might Be Settlement
Now you know that foundation heave is the opposite of settlement i.e. it’s a slab moving up instead of sinking down. The main cause is extra moisture in the soil, and the fix usually starts with finding and controlling that water source. But what if you now think it’s settlement or you just can’t tell??
At Anchor Foundation Repair, we may not see heave every day, but we do know how to recognize it and help you sort out the problem without making costly mistakes. Our goal is always to give you clarity and a practical path forward with your home’s foundation.
If your issue feels more like settlement after reading this article, it definitely makes sense around here and we can help here for sure.
If you want to learn more about how to spot foundation problems the way we do, check out this article: How To Know If Your Home Has Foundation Problems.
