Originally posted 5/7/20, updated 9/10/21
It could be that you’ve found cracks in your basement wall, and you’re researching solutions. Maybe you read our blog on DIY Home Inspection, surveyed your home, and now have concerns. Perhaps a friend or neighbor suggested you contact us and you’ve used our symptom checker.
Whatever virtual road you have taken, your search has clearly been driven by a need to learn more about carbon fiber straps. (And sorry! That pun was NOT intentional.)
Acculevel has been repairing foundations and restoring homeowners’ peace of mind since our beginning in 1996. We have installed straps in thousands of homes, and we proudly warranty our work for the life of the structure.
We’re going to explain what carbon straps are, why you need them, how they work, and what they cost. This will help you understand what is involved in this type of repair, how to choose the right contractor for your home.
What Are Carbon Fiber Straps?
Carbon fiber straps are a product used to reinforce and stabilize a foundation wall. Most of these straps are made by using solid carbon, but this is not the best method to use. Carbon by itself is very hard and smooth, so it will not easily adhere to the wall, nor to the epoxy. Think of it like trying to glue a smooth piece of plastic to another surface: no matter how long you let the glue dry, you can peel that plastic away.
In order to make the strap a cohesive part of the foundation, you need an unbreakable connection between carbon, epoxy, and concrete.
The strap we use is made of kevlar-grade carbon, and the fibers are woven together. This woven pattern creates small spaces in the carbon fiber strap, and these spaces are what allows the epoxy to fully penetrate through the strap to the wall. Once the epoxy is smoothed on the surface, it works like rivets, locking the strap onto the wall in thousands of spots. This particular type of carbon fiber straps is made by Fortress Stabilization Systems; it is the strongest strap available and is backed by the best warranty in the industry. When we work on a customer’s home, we treat it as if it were our own. We warranty our strap repair for the life of your structure.
This is a close-up of a carbon fiber strap.
The picture above shows the type of carbon fiber strap that we use at Acculevel. This is not what every company uses; not all carbon fiber straps are created equal. You will want to ask a potential contractor what type they plan to install in your home.
Why Do You Need Carbon Fiber Straps?
You need carbon fiber straps when you have a badly cracked or slightly bowed wall. Typically, a basement wall begins to “give way” when hydrostatic pressure develops outside your foundation wall.
Hydrostatic Pressure: the term used to describe how the force water exerts against something. In this case, there’s so much water in the ground outside your home it has fully saturated the soil. This soil expansion – and the water pressure within it- is what damages your foundation. We delve deeper into this topic in another blog specifically about hydrostatic pressure and why it matters to homeowners.
The important thing you need to understand is that some soil types are more susceptible to hydrostatic pressure than others. Soil with a significant amount of clay in it is called expansive soil. If you have expansive soil, or you are experiencing water intrusion along with your bowing wall, you may need to incorporate waterproofing into your repair plan.
We train our project advisors to thoroughly evaluate your home and its symptoms, so that we can offer you a whole-home solution. If you have expansive soil and significant wall cracks, the best option for you may be a combination of services. You need carbon fiber straps to repair the wall that is bowing right now, because it’s a safety concern. But if you add water drainage to your basement, you could also relieve the hydrostatic pressure and prevent it from later damaging your other walls.
Early Warning Signs of a Bowing Wall
A basement wall doesn’t usually bow immediately. The first sign you normally see is a horizontal crack running along the wall. If your basement is made of concrete block, the crack may be more of a zig-zag or stair-step pattern.
This photo was taken by an Acculevel project advisor during a free estimate appointment. Both stair-step and horizontal cracks are visible.
If the wall is only cracking, or is bowing less than 2 inches, carbon fiber straps can be used to reinforce the wall and restore stability. If there are few obstructions outside the foundation, excavation can be done to straighten the wall before securing it.
This is an illustration of Fortress Carbon Fiber Straps
If your wall is bowing more than 2 inches, other repair methods are going to be required. For more information on those, you can review our article on the best way to repair a bowing wall or our comprehensive foundation guide.
How Do Carbon Fiber Straps Work?
The straps are secured to the wall with an epoxy application. This epoxy seals the wall and fuses the strap to it. Properly secured, this bond is permanent and can hold up to a tremendous amount of force. To demonstrate the strength of a carbon fiber strap, we had our Sales Director help us with the video below:
The straps have specially designed anchors for use at the top and bottom of the wall. The top anchor is attached to the rim joist; this is essentially the lowest layer of the main (or first) floor of the house. This is done to stop the top of the wall from sliding inwards. The bottom anchor attaches to the floor of the basement, which is essential to prevent any shearing (sliding) of the wall at the bottom.
Once these are installed, your wall is not going to bow any more. The Acculevel warranty guarantees that the wall is stable and secure, for the life of the structure. Please note that this warranty is not standard in our industry, and make sure to ask your contractor what is covered and for how long.
What Do Carbon Fiber Straps Cost?
This answer can vary, depending on the size of the wall. At Acculevel, carbon fiber straps are approximately $600 to $700 each. A strap should be installed approximately every 4 feet along a bowing wall. If your basement wall is 24 feet long, you will need 5 carbon fiber straps, and that’s an estimated $3,000-$3,500.
There are definite benefits to taking action early.
- If you install straps, the installation is limited to inside your basement. It will only generate noise and very minimal dust. (We use a dust collection system as part of our installation process.)
- There’s no need to excavate your yard or uproot any landscape (unless you want the wall straightened).
- No holes are penetrated through the foundation wall.
- Once the installation is complete, you can paint over both the straps and wall, and greatly reduce the visual impact as well.
Most significantly? Carbon Fiber Straps are the least expensive way to repair a bowing foundation wall. If you wait until you need anchors or tiebacks, both the expenses and the mess add up quickly. We explore the costs of delay in another blog, that gives you the escalating costs of not taking action.
Do You Need Carbon Fiber Straps?
Then you need to find an experienced local foundation company and make an appointment. Before you sign a contract for any service, you should always verify the company is reputable, insured, and accredited by the Better Business Bureau.
If you live in Indiana or the surrounding states, contact Acculevel. Established in 1996, we specialize in foundation repairs and will treat your house as if it were our own.
Not sure how to hire a contractor, or what to ask? We have additional resources available to you:
- A detailed checklist of questions you should ask a contractor
- 3 steps to getting the best price for home repairs
- Advice on how to safely meet with contractors under difficult circumstances (like the COVID-19 outbreak)