Crawl Space & Foundation Repair in Knoxville, TN

Have you noticed that your home smells particularly humid and musty during the summer? If so, you might need to check the condition of your basement or crawl space. Lack of insulation and open airways make it so that the air from your foundation makes it up towards the upper levels of your home. Warm air is constantly trying to invade cooler spaces, the hot air from the outside makes its way into your foundation. Because warm, damp air is lighter than cold, dry air, whatever air is in your ventilated foundation is the one you breathe throughout your home.

Summers in Knoxville are extremely hot and humid. This is a time in which mold growth is persistent and pests are more likely to make a home out of your damp, warm basement. All the mold, animal droppings, cockroach skins, and stuffy air that exists in your foundation permeates through the airways and occupies the rest of your home. This is why your home is terrorized by bad smells during the summer. What you need to do to stop this problem is close off your crawl space or basement and make sure they’re properly insulated.

Our thick and durable vapor barrier can be applied to basements and to completely encapsulate crawl spaces so water vapor doesn’t raise the humidity levels. Basement insulation should be checked to make sure it is still functional. Some insulation materials are absorbent and cease to work properly after absorbing too much moisture. For complete crawl space insulation, our rigid thermal insulation panels are made of a more reliable, reflective material that keeps the hot air inside and away from your living space.

Although there are five types of foundations that a home can have, in a southern state like Tennessee (where winters can still see below freezing temperatures) slab, crawl space, and basement foundations are the three most common ones. If you have a crawl space or basement, your floors are cold because of poor insulation. In the past, it was believed that crawl spaces and basements needed to be vented in order to air out the bad smells and humidity, so insulation was rarely installed. However, open foundations affect how the air moves through your home and changes the temperature of your floorboards. The average house in Knoxville is 45 years old, so it’s very likely you’re living in a home with either poor or no insulation.

No insulation means that warm air can rise through your home while cold air goes down to your foundation due to the stack effect. Your floor is cold because your foundation is cold. Even if insulation was installed in your home, if the material is damaged, it won’t be able to keep the warm air from escaping. Insulation made from fiberglass is an absorbent material that absorbs heat, but also absorbs moisture. If your foundation isn’t waterproofed and you have fiberglass insulation, chances are, it isn’t doing its job.

You are more likely to have cold floors if you have a slab foundation. With a slab foundation, if the foundation is cold, your floor is cold since there’s nothing between the concrete and the floor. Very few construction companies think about thermal control on slab foundations because all they care about is making sure the foundation is built up to code. This means that you will have to get in contact with experts that are able to install heating systems around your slab foundation to fix your cold floor problem.

The word “hydro” means water and “static” is a synonym for still or steady. The term hydrostatic pressure perfectly illustrates the effects still groundwater has on your foundation and why it is so important to keep an eye out for it. 

Hydrostatic pressure is something you might not know you need to watch out for as a homeowner, but once you know about it, you’ll be more vigilant. It’s the kind of problem that many don’t think about until it affects their foundation significantly. Knowing what it is and what it does to your basement walls will allow you to understand why your walls are bowing and what the correct action to take is. 

• What It Is  

The soil underneath your home isn’t completely dry, even if the topsoil on your lawn is. The ground below is almost always saturated with water, especially in places like Knoxville and Nashville, TN and Huntsville, AL, which have clay soils. Clay soils are able to retain water very well. Other places, like Chattanooga, TN and Mobile, AL, have sandy loam soils, which drain incredibly well, so hydrostatic pressure isn’t a big concern in these areas unless the yard drainage is especially terrible. 

When groundwater begins to flow towards your home, it stops once it means resistance in the form of your basement wall. It accumulates against the wall and the weight of the water begins to put pressure on the wall. No matter how tough a concrete wall is, it will begin to bow inwards once that pressure becomes too much. In the simplest terms, hydrostatic pressure is the weight of water against a basement wall. 

• What Hydrostatic Pressure Does to Your Foundation  

Hydrostatic pressure is a serious threat to your entire home. Even though its effects are mostly seen in the basement, it does affect the structure of the entire house. As the basement wall bends inwards due to the pressure of the accumulated groundwater, it begins to crack. The cracks allow the water to seep through the concrete and infiltrate your basement. Flooding is most common in the wall-floor joint, which is where you’ll see most of the water come from. 

Your basement wall is a part of your home’s foundation. The second a foundation begins to have structural problems; the effects will be felt elsewhere. You might notice your floor begin to sink closer to the wall. Any columns that relied on the walls to support the ground floor will begin to fail, which means that the walls above will also experience issues with cracking, bending, and breaking. 

With basements and crawl spaces, there are many waterproofing methods that can be implemented to not only repair these spaces, but also future proof them from the effects of soil expansion. Waterproofing basements and crawl spaces involves installing new insulation material (if needed), encapsulating them with a vapor barrier, and installing an interior drainage and a sump pump, as well as a dehumidifier. However, all of this is possible when there’s space between the ground and the first floor of a house. The only thing separating the ground from the first floor of a house with a slab foundation is the flat, concrete slab itself, so no drainage system installations are possible. So, what kind of waterproofing methods exist for existing slab foundations?

Unfortunately, existing slab foundations cannot be waterproofed. Your home’s ductwork and pipes can be found under your slab, so any kind of tampering with the foundation can damage your HVACs ductwork and the drainage system around your home. If you’re building a new foundation, drainage tiles and pipes can be installed, though it makes installation of electrical systems and air vents a lot more difficult, so many construction crews don’t like to do it. Other water drainage systems that exist for slab foundations can only be installed from the outside. Drainage tiles and pipes are typically installed as the foundation is being built because installing them on an existing foundation would mean disrupting the foundation and risking slab settling.

Prevention is your best bet when it comes to slab waterproofing. This means making sure water drains away from your foundation as much as possible. If your slab foundation has gotten to a point where it’s cracked or settling, there are multiple repair methods that can be used depending on the condition of your foundation. Slab piers are driven deep into the ground so your foundation is lifted and supported by strong, load-bearing soil. A special polyurethane foam can also be used to lift the slab foundation so you no longer have to live in a home with a sinking floor.

Soil erosion is the cause of most settling problems. It’s defined as the displacement of the top layer of soil, which can occur for several reasons. All homes are built upon soil that is compacted to form a dense foundation that is stable enough to support the structure. However, if the topsoil is disturbed, not only will it be unable to support the concrete, it will also allow more water to filter through, leading to foundation problems. To protect your home’s structure, you need to mitigate the damage caused by soil erosion, since it’s impossible to fully prevent it.

Soil erosion is inevitable and can be triggered by things way out of our control, mostly things to do with nature. For example, due to its proximity to the New Madrid seismic zone, western Tennessee is more prone to earthquakes than eastern Tennessee. However, this doesn’t mean that the effects of the earth tremors don’t affect the soil in eastern cities like Knoxville. Heavy rainfall also encourages soil erosion since each drop of water creates a small crater in the soil. Given Knoxville’s humid subtropical climate, it’s difficult to stop splash erosion.

Because this is such an unavoidable problem, the best thing you can do as a homeowner is prepare your foundation and take certain prevention methods. Waterproofing your foundation raises the value of your home, saves you the trouble of a flooded basement, and discourages foundation settling. Your yard should also have the proper drainage installations to avoid water erosion as much as possible. You can contact a landscaping expert to inspect the yard, determine its grade, and re-grade if needed so the topsoil doesn’t wash away every time it rains. Consider increasing the vegetation around your yard as well, since this can act as cover from wind and rainfall.

Concrete steps are oftentimes an overlooked part of a household, even though they are pretty important. When structurally sound, they provide secure access to certain parts of the house. However, when something is wrong, they are no longer safe to use and become a safety risk. If your concrete steps seem lopsided and wobble every time you use them, they are most likely settling. In order to ensure safe passage through your home, you need to get them repaired, which can be done easily by your local experts.

It’s important that you contact professionals when wanting to fix concrete steps. Almost all the DIY fixes you’ll find online for concrete settling focus on visually repairing the concrete without addressing what caused it to settle in the first place. Concrete steps settle due to soil expansion and shrinkage. If your soil has eroded to the point it cannot hold up the concrete, patching up cracks on the steps or leveling them by applying cement won’t actually fix the settling. The only way to truly fix the issue is to use polyurethane injections to lift the steps.

At AFS, we drill small holes in the concrete and inject a polyurethane foam that lifts settled concrete. It’s the easiest, most efficient way to lift concrete, and because the polyurethane foam creates a barrier between the concrete and the soil, the soil conditions never affect the concrete again. The holes drilled to do the job are small, so your steps end up looking untampered with when the job is finished. The foam is firm, but light enough that it doesn’t place pressure on the soil, unlike the cement slurry used in mudjacking. Polyurethane injections require special materials, knowledge, and equipment, so contacting your local experts is the best thing you can do to repair your steps.