Walk into most buildings and you probably won’t notice them, but expansion joints are working overtime to keep structures from tearing themselves apart. Meanwhile, if you own an older home in the Dallas-Fort Worth area, there’s a good chance you’re sitting on top of a pier and beam foundation. By understanding how it moves, it could save you from some serious headaches down the road.
In this blog, we’ll break down what expansion joints actually do, why they matter, and how pier and beam foundations can can affect them.
What Exactly Are Expansion Joints?
Think about what happens to a sidewalk in Texas. Summer hits, temperatures climb past 100 degrees, and that concrete wants to expand. Winter rolls around, and the concrete and soil contracts. Without anywhere for this movement to go, you end up with cracked, buckled concrete that looks like it went through an earthquake.
That’s where expansion joints come in. They’re intentional gaps built into structures. They are narrow spaces between building sections that give materials room to move. Temperature changes make building materials expand and contract throughout the year, and these joints absorb that movement without letting stress build up inside the structure itself.
You’ll find expansion joints running vertically through buildings, from the foundation all the way up through walls, floors, and the roof. They’re strategically placed at spots where different building sections meet, where there are directional changes in the structure, or where one material meets another with different expansion properties. Basically, anywhere the building is likely to want to move independently.
The material filling these joints needs to be flexible enough to compress when the building expands and stretch when it contracts. Traditional options included asphalt-based fillers, but modern buildings often use polymer-based solutions or specialized rubber compounds that can handle significant movement without breaking down.
Expansion joints aren’t just about temperature. They also help buildings handle vibrations from traffic or machinery, accommodate settling as the structure ages, and in seismically active areas, they’re crucial for earthquake resilience. Buildings in earthquake zones often have wider expansion joints specifically designed to absorb those violent lateral movements.
Why Foundations Usually Skip the Expansion Joints
If expansion joints are so important, why don’t we see them in foundations? Good question. Turns out, foundations are buried underground where temperature swings are minimal compared to what’s happening above ground. The soil acts like insulation, keeping foundation temperatures relatively stable year-round.
That doesn’t mean foundations don’t move, though. They absolutely do, just for different reasons than thermal expansion. And that brings us to pier and beam foundations, which have their own unique personality when it comes to movement.
How Pier and Beam Foundations Work
If your home was built before the 1960s in Texas, odds are decent you’ve got a pier and beam foundation. Instead of a solid concrete slab, your house sits on a series of vertical supports (piers) that hold up horizontal beams, which in turn support the floor joists and everything above them. There’s a crawl space underneath, where utilities can be connected
These foundations were popular for good reason. They handle our problematic clay soils pretty well, they keep homes elevated above potential flooding, and they make it easy to access plumbing and electrical systems for repairs. But they’re not immune to problems, and when they start shifting, things can get ugly fast.
The Clay Soil Problem
Our Dallas-Fort Worth clay soil swells up like a sponge when it gets wet and shrinks back down when it dries out. This isn’t a minor adjustment. Soil that can change volume significantly between rainy seasons and droughts.
When soil expands beneath a pier, it pushes that pier upward. When it contracts, the pier can sink or tilt. Multiply this across dozens of piers under your house, each one potentially moving at different rates depending on soil moisture directly beneath it, and you’ve got a recipe for differential settlement.
The worst part? This cycle repeats every year. Maybe multiple times per year if we get a particularly wet spring followed by a scorching summer. Each cycle does a little more damage, like bending a paperclip back and forth until it eventually snaps.
Poor Installation and Aging Materials
A lot of pier and beam homes were built when codes were different and materials weren’t what they are today. Sometimes piers were spaced too far apart to properly support the load. Sometimes they weren’t anchored correctly. Sometimes the wrong materials were used for the soil conditions.
Wooden piers deteriorate. Concrete develops cracks. Shims compress and degrade. Steel piers can corrode if exposed to moisture. Time takes its toll on everything, and foundations are no exception.
What Happens When a Pier and Beam Foundation Shifts
The problems start subtle and get progressively worse if ignored. Here’s what you’re likely to notice:
Floors that feel wrong. Maybe there’s a spot that bounces when you walk across it. Or the floor slopes noticeably from one side of the room to the other. Some areas might feel spongy, like you’re walking on a slightly soft surface instead of solid flooring. These are all signs that the support beneath that section has shifted or failed.
Doors and windows acting up. When foundation piers shift, they pull the frame of your house with them. Doors that used to close smoothly suddenly stick or won’t latch. Windows become difficult to open or won’t stay open. You might need to force them, or they might swing open or closed on their own because the frame is no longer level.
Cracks appearing everywhere. You’ll see diagonal cracks shooting across drywall, often starting from the corners of doors and windows where stress concentrates. Cracks might appear in the ceiling, especially where walls meet. Exterior brick can develop stair-step cracks that follow the mortar lines. Floor tiles crack or pop loose. These cracks are your house screaming that different parts of it are trying to move in different directions.
Gaps that shouldn’t exist. Cabinets start pulling away from walls. Crown molding develops visible separation. Baseboards show gaps. Countertops might separate from backsplashes. All of these are signs that the walls themselves are shifting as the foundation moves beneath them.
Plumbing problems. When piers shift, they can stress plumbing lines running through the crawl space. You might develop leaks you never had before. Drains might start flowing slower because pipes are no longer at the proper angle. In severe cases, pipes can actually separate at joints.
Why You Can’t Just Live With It
Some homeowners figure they can adapt to a few stuck doors and uneven floors. Maybe they’ll deal with it when they sell. Bad strategy for several reasons.
First, foundation damage keeps getting worse. It’s not a static problem that reaches equilibrium. Every wet-dry cycle in the soil, every year of additional settling, every bit of continued wood rot just compounds the issue. What costs a few thousand to fix today might cost tens of thousands if you wait.
Second, it affects everything in your house. HVAC ducts in the crawl space can separate or develop leaks, making your system work harder. Plumbing problems can cause water damage. Uneven floors stress every system and component attached to them.
Third, buyers aren’t stupid. When you do decide to sell, any competent home inspector will flag foundation issues immediately. You’ll either need to fix them before selling, offer a massive price reduction, or watch potential buyers walk away entirely. Foundation problems are usually deal-breakers or major negotiating points.
Getting Ahead of Foundation Problems
The good news? Pier and beam foundation issues are fixable, especially if you catch them early. Professional foundation repair companies can install new piers, shim existing ones to restore level, replace rotted beams, install better drainage systems, and address whatever specific problems your foundation has developed.
Even better, you can prevent a lot of these problems with proper maintenance. Keep gutters clean and functional so water doesn’t pour around your foundation. Grade your yard so water flows away from the house. Consider installing a drainage system if you have persistent moisture issues. Maintain consistent soil moisture with soaker hoses during dry periods to minimize expansion-contraction cycles. Keep your crawl space ventilated and address any plumbing leaks immediately.
At Maestro’s Foundation Repair, we’ve seen every kind of pier and beam problem our North Texas clay soil can dish out. We know how foundations shift, what causes different types of damage, and how to fix them so they stay fixed. Our preventative maintenance services can also help you avoid problems before they start, including proper drainage systems, gutter installation, and soaker hose setups that keep soil moisture consistent.
We offer thorough inspections and honest recommendations, with a one-year warranty on our labor and workmanship. Your home’s foundation is literally holding up everything else. Give it the attention it deserves, and it’ll keep protecting your investment for decades to come.