Interior Foundation Repair: Signs, Causes, and What Actually Works

When your walls start cracking inside, or doors stick for no reason, it’s not just bad luck—it’s often your interior foundation repair, the process of fixing structural issues inside a home’s base to prevent further damage. Also known as foundation stabilization, it’s not a cosmetic fix. It’s what keeps your house from slowly sinking, tilting, or splitting apart over time. Most people think foundation problems show up as big cracks outside, but the real red flags are usually inside: diagonal cracks along drywall, uneven floors, gaps around window frames, or doors that won’t close properly. These aren’t just annoyances—they’re signals your foundation is moving.

What causes this? It’s rarely one thing. In older homes, it’s often soil moisture, the amount of water in the ground under your house, which expands or shrinks with weather. Clay soil swells when wet and pulls away when dry, putting pressure on your foundation. In newer builds, it’s often poor drainage or improper grading. Water pooling near your walls is the #1 killer. And let’s not forget poor construction—shallow footings, weak concrete, or inadequate reinforcement can show up years later as interior damage. You can’t fix this with paint or filler. You need to understand the root cause before you spend a dime.

Not every crack needs a full repair. Hairline cracks? Often just settling. But if they’re wider than a quarter-inch, getting longer, or accompanied by sticking doors and sloping floors, it’s time to get a professional in. The good news? Most interior foundation repairs don’t mean tearing up your whole house. Techniques like epoxy injection for cracks, steel piers for sinking sections, or interior drainage systems to manage water are common and effective. And yes, foundation repair cost, the typical price range for fixing structural damage inside a home can run from $1,500 to $10,000 depending on the damage—but ignoring it can cost you 10 times that in lost value or safety risks.

There’s no magic solution. Some companies push expensive slabjacking or full underpinning when a simple drainage fix would do. Others downplay serious issues to win a job. The key is getting a clear diagnosis: a written report, photos, and a breakdown of what’s wrong and why. Don’t trust a guy with a clipboard who says "it’s fine" without showing you the evidence. If your home is over 20 years old, or you’ve had heavy rains lately, you’re at higher risk. And if you’re planning to sell, fixing these issues now can mean thousands more in your pocket later.

Below, you’ll find real stories from homeowners who’ve been there—what they paid, what went wrong, what actually worked, and what they wish they’d known before calling a contractor. No fluff. No upsells. Just the facts you need to decide if interior foundation repair is right for your home.