Have you noticed that every company that represents a carbon fiber strap or sheet product says theirs is the best? How are you ever going to be able to figure out the truth? In reality, all carbon fiber products are pretty good IF they are installed properly and used as they were designed to be. Generally speaking, there are 3 types of carbon fiber reinforcement, fabric, rigid straps, and solid plates. The epoxy used varies with the type of carbon used.
Carbon fiber fabric, a thin, flexible strap or sheet, is generally on the lower end of the strength spectrum, around 50,000 psi. Its advantage is that it is very flexible and can easily conform to any configuration. It was initially designed to strengthen and reinforce concrete pillars and odd-shaped construction as it can be wrapped around and tucked into these shapes. Often the repair application requires more than one layer of the carbon fabric to be strong enough. Generally, the thinner carbon fabric is applied to the repair surface like wallpaper is applied to a wall. The epoxy which is used with this type of carbon fiber is designed to adhere to bare concrete which has never been painted. A quick surface grinding will remove any roughness from the surface first. The wall section is then cleaned and the liquid epoxy is rolled on. The carbon fabric is soaked in a bucket of liquid epoxy and then pasted on the wall. A regular roller is used to squeeze out excess epoxy and air pockets. Fabric carbon fiber is great for unusual surfaces, but not as good as the thicker rigid carbon fiber straps for flat surfaces such as a basement wall. Not only is the carbon fiber itself less strong, but the epoxy bond is less secure, especially if the surface has been previously painted and some paint remains in the concrete pores or if the installation is not done perfectly and air bubbles remain. It is more challenging to ensure all air bubbles have been squeezed out because the installer cannot see through the fabric. As a result, this type of installation is more prone to delamination.
Solid plate carbon fiber product is brutally strong, approximately 500,000 psi. It is designed for very high-strength reinforcing, usually commercial applications. The epoxy used to bond it dries slowly and often has dangerous VOC (volatile organic compounds) fumes emitted during application and curing. Again, the skill of the installer is critical to ensure there are no air bubbles beneath the carbon. This is the most expensive carbon product and is generally not used to reinforce basement walls.
Fortress hybrid straps combine all the advantages of carbon fiber and KEVLAR®to deliver a product that boasts a high strength-to-weight ratio and dimensional stability in addition to remarkable impact-, abrasion-, and fatigue-resistance. The strength of this carbon fiber is over 234,000 psi. There are several advantages to utilizing Fortress hybrid straps for basement wall stabilization. It is the only carbon fiber product that meets I.C.C. Standards for this industry. Installers are required to be certified by Fortress. A Fortress certified installation means your repair will meet all building code requirements and will pass all future inspections. A transferable lifetime product warranty is standard. The special epoxy has no VOCs so consequently there will be no fumes emitted from the installation. The epoxy is designed to adhere to concrete walls that have been previously painted. It is also designed to be able to be installed on a wall that is not perfectly dry from outside water intrusion. After curing for 24 hours the epoxied wall strap becomes part of the wall and nothing can remove it. Hydrostatic forces cracking and bowing your wall can never be great enough to overcome the strength of this strap. Because this strap is a weave design, the epoxy which binds it to the wall will push through the weave, like a million rivets. The open weave also allows the installer to easily see and remove any air bubbles, unlike the solid cloth-like carbon fiber and the solid plate carbon fiber. Fortress carbon fiber is manufactured in the United States. Top and bottom anchors are standard.