You’ve been reading up on the real and false signs of foundation settlement and foundation problems, but you’re seeing some things that are *a little bit different* than what’s on these lists of telltale signs.
You still feel fairly certain that you’ve got foundation issues though. So why aren’t your symptoms matching up? Well . . . you might have interior foundation settlement.
At Anchor Foundation Repair, we have been assessing foundation problems and repairing foundations in Bryan, College Station, and other surrounding communities like Caldwell and Madisonville for 35+ years. There are a few signs we see in homes that point more to interior foundation settlement vs. your typical, everyday foundation problem signs.
This article will explain what interior settlement means and outline signs unique to this kind of foundation problem that you might see in a home. We will also discuss how foundation repair is different for home interiors and what repair options are available.
What Is Interior Foundation Settlement?
Most of the time, foundation settlement and problems can be fixed by adding supports (called underpinning in engineering terms) only under the perimeter of the home. An example repair plan showing only the need for exterior “underpinning” is shown here.
In 90% of repairs that we do, homes need foundation support added only around the exterior of the home. But in 10% of homes we repair, the areas underneath the middle of the home need support added too.
Interior settlement is not a problem inside the slab foundation itself, it’s a settlement problem underneath the “inside” of your home.
So, we’re talking about areas under your living room floor, down a hallway, and/or underneath load-bearing walls throughout the underside of the *interior* areas of the home. Hence the name, interior foundation settlement starts to make sense.
Here’s a diagram of a home foundation repair plan that needs both some interior and some perimeter areas of the home supported. The blue dots and squares are where the support piers or pilings are placed under the exterior of the home. The triangles are where interior supports would be added.
There are times when only a portion of the home needs interior foundation support along with some exterior work. But within that 10%, we often have to add underpinning to the entire foundation.
Why is Interior Settlement Less Prevalent and What Causes It?
You may wonder why it is that 90% of homes need the exterior/perimeter of the home supported and only 10% need interior work. Good question.
There is one main reason that interior home foundation settlement is much less common: soil moisture levels do not fluctuate as much (or at all) under the center of homes. So interior settlement is much rarer than exterior settlement where water has greater influence over the home’s structure.
But then, grade beams under the center of homes are not required to be as strong, so sometimes they were not made strong enough. Even with less impact from moisture levels, insufficient support from grade beams can cause settlement issues under the interior of your home.
Support issues happen more prevalently in homes that were built from the 60s to the 80s when slab-on-grade foundations were *a newer thing* and they didn’t know as much about what would work best. Newer building codes have been continually improved, but they still don’t require interior grade beams to be as strong or deep as exterior grade beams.
Top 6 Signs of Interior Foundation Problems
The most common signs of any type of foundation settlement or problems are things like diagonal cracks in drywall coming off of door and window frames, stair-step cracks in exterior brick, doors that don’t lock or latch properly, and trim separations where wood trim is popping off or coming away from its originally secured location.
We have a whole article that covers the top signs of foundation issues for you to check out if you need to.
We’ve mentioned that 10% of homes we work on have interior settlement problems in need of repair. Signs of interior foundation problems might present differently than the usual telltale signs of foundation issues.
We’ve identified 6 signs that are more indicative of interior foundation settlement we see in homes, here they are in no particular order.
- Horizontal Brick Cracks
- Brick Cracks or Expansion Joints that are Wider on the Bottom than the Top
- Gapping Between Brick Frieze and Exterior Wall When Viewed from Below
- Diagonal Wall Cracks that Point Towards the Center of the Home
- Gaps Between Walls and Floors or Walls and Ceilings
- Door Gaps Decreasing or Sticking Nearer the Center of the Home
Now that we have listed them, we will explain them in more detail and in contrast to the usual signs of foundation settlement.
1. Horizontal Brick Cracks
Usually, brick cracks tend to be in a stair-step pattern on homes with foundation settlement. But when there is interior settlement, the brick cracks can often (but not always) run horizontally.
This is because the area where the foundation is sinking is not directly underneath the exterior beam. The pressure is coming from farther into the center of the home that creates a sag in the middle of the wall.
2. Cracks Wider at the Bottom Than the Top
Normally you don’t really see vertical cracks that indicate exterior foundation settlement. They are usually running in the stair-step pattern diagonally. But if you are seeing more vertically oriented exterior brick cracks or even your expansion joints in the brick that have a larger gap at the bottom than at the top, that can be a specific indicator of interior foundation settlement.
When the foundation sinks in the center of the home, it creates a sag on the exterior wall. Then, the sinking action can cause the cracks to be wider at the bottom and narrower near the top of the wall.
3. Gapping Between Brick Frieze and Exterior Wall
Brick frieze is a trim piece between the top of the brick veneer and the woodwork above it, it’s a transition piece covering the changeover between the brick and wood. With typical foundation settlement under exterior walls, the brick frieze can come apart at the corners because the brick begins to lean outwards.
But with settlement on the interior of the home, the brick frieze often does something else. Rather than coming apart at the corners (as shown in the picture) from the brick leaning out, a gap will be created between the frieze boards and the brick as the wall leans inwards instead.
Somewhere along the middle of the wall, the brick frieze trim board will look like there is a gap in between it and the brick wall behind it. You can only see this when you are directly under the gapped area and look upwards. You might not notice something like this just standing away from your house and looking towards an exterior wall.
Homeowners will often feel the need to stuff this gap with insulating foam or sealing caulk to keep the critters out. But it’s more than just a space where *things* can get in your house, it can also be a sign of interior foundation settlement.
4. Diagonal Wall Cracks that Point Towards the Interior of the Home
Usually in the telltale signs of foundation settlement, the diagonal cracks you see on your interior walls will point towards (or head in the direction of) an exterior wall where the settlement is happening. For interior settlement, the diagonal cracks point inwards towards the middle of the home instead.
So you will still see diagonal cracks in drywall coming off of door frames, they will just be pointing in a different direction in relation to the home’s exterior walls.
This happens because the area that is sinking is under the center of the home. When a home is settling in the middle, the interior walls are dropping lower than the exterior walls. Cracks always point to or head in the direction of where the settlement is occurring.
If you have diagonal drywall cracks that both run towards the center of the home and towards the exterior, then you likely have both interior and perimeter settling problems, or seasonal settlement that changes year to year.
5. Gaps Between Walls and Floors or Walls and Ceilings
With typical foundation settlement, you mostly see *the action* on vertical surfaces in the home. But with interior settlement, you start to see things happening between the horizontal and the vertical. This is because the directional surfaces are wanting to do different things.
The floor wants to sink, but the walls want to stay in place due to interconnected parts. Or the walls want to sink because they are riding along with the foundation and the ceiling doesn’t want to go with them due again to the interconnected nature of homes.
Homes are built layer upon layer, some layers are tied together more tightly than others and the stronger bonds will win and the weaker connections will get pulled apart and start gapping or pulling connections between the horizontal and the vertical surfaces.
We’ve got some pictures here that show a significant gap between the floor and the baseboards inside a home. Keep in mind that not every example is this extreme.
6. Door Gaps Decreasing or Sticking Nearer the Center of the Home
Doors sticking or not closing or latching properly is a typical sign of foundation settlement. It doesn’t take much movement to begin to affect a door’s ability to match up with its frame.
What’s different about door frames and interior settlement is basically what corner of the door frame is being affected. Is it the corner closest to the middle of the home? If so, then it could mean interior foundation settlement issues.
3 More Signs That Might Indicate Foundation Settlement
There are a few other signs that *might* point to interior foundation settlement, but they are not as common. You would likely have some of the other things listed above present in your home, along with one of these signs. So, we won’t spend a ton of time explaining them, but here they are . . .
- Hollow sounding tile floors or tile floors that tent or pop
- Porches that don’t drain heavy rain away properly
- Corner Pop
These symptoms can have other root causes too. So they are not always definitive signs of interior settlement, they could be caused by something else.
How is Foundation Repair Different for Homes with Interior Issues?
Well, foundation repair can be a lot different when you have interior settlement vs. only exterior settlement. Mostly, it’s because the repair team will be inside your home a whole lot more. The repair project will cost quite a bit more and will take more time to fix a home with interior settlement. Flooring can be impacted, requiring repair or replacement.
You might even have to move out during the foundation repair process. None of this sounds like the *greatest news* in the world, unfortunately. Interior foundation problems are more to be concerned about. But you do have some options depending on the method you choose for interior settlement repairs.
What Options Are Available to Handle Interior Foundation Repair?
You have to weigh your options when handling homes with any foundation problems. You need to decide what is most important to you in getting it done. Sometimes the biggest factor is cost or time. Some homeowners want a method that is the least intrusive or the longest lasting. No one method can offer all of these things perfectly.
The drilled pier method that we use takes a longer period of time and higher cost, but has the longevity that many homeowners are looking for. Concrete pressed piles can be cheaper and quicker, but some companies could still break through your floors to get it done.
Other pressed pile companies might tunnel under your slab to install the supports but all pressed pile methods can be prone to longevity issues. I’m starting to feel like we need a whole other article on just this topic because there’s a lot to it . . .
We often suggest a mix of methods to homeowners with interior foundation settlement issues. It’s a combination of traditional foundation repair on the exterior, with polyfoam injection aka polyjacking under the interior. This helps you *at least* get the best of two foundation repair worlds.
More About Polyjacking Used in Foundation Repair
All we were trying to do with *this here article* is talk about signs of interior foundation settlement, and we’ve done that. We’re getting into new territory by bringing up methods of foundation repair for handling it. So let’s try and wrap this up for ya. . .
At Anchor Foundation Repair, we are dedicated to helping Brazos Valley homeowners find the options that work best for them through education and 100% transparent information. Knowing that interior foundation work can be a huge undertaking, we’re not opposed to recommending another repair process if it makes the most sense for you and your home.
Polyjacking is a less intrusive method for handling interior foundation settlement and I bet you might want to know more about it. Check out this article explaining, “What is Polyjacking? The Poly Foam Injection Used in Foundation Repair,” for the full rundown.