# Understanding the Carrying Capacity of Polyurethane Foam > Would you believe there is a type of foam that can be as hard as concrete, yet far lighter? What if I told you it carries, or stabilizes, a building? _Brian Dalinghaus ยท 2023-04-26_ Video: [Polyurethane Expanding Foam in Foundation Repair](https://www.youtube.com/watch?v=bdnPxOZoADA) --- Would you believe there is a type of foam that can be as hard as concrete, yet far lighter? What if I told you it carries, or stabilizes, a building? ![Polyurethane injection gun resting on a mound of cured white foam on a concrete floor](/assets/blog/carrying-capacity-polyurethane-foam-repair-2.webp) I know it's hard to believe, especially when the types of foams we use are for shaving or memory foam feeling like you're sleeping on a cloud. But polyurethane foam is used for construction, as well as many applications. Name a category. You'll likely find out how polyurethane applies. Dalinghaus Foundation Repair has completed more than 2,000 foundation projects since 2011, and polyurethane has carried a large share of that work. After many years in construction, we understand how this stuff works and how much it can carry on its back. Its many applications are amazing when put to work. ## What Is Deep Injection With Polyurethane? It's a pretty cool process for foundation repair Dalinghaus can do. This involves putting tubes into the soil under your home or business with an injection gun to put in polyurethane foam. Voids and microvoids will be filled at different layers and densify the soil. The primary function of deep injection with polyurethane foam is to densify soil and stabilize your home or business. ## Why Is Polyurethane Foam so Awesome? When it comes to being used in many applications, polyurethane foam is excellent for purposes like void fill, soil stabilization, and releveling. You're essentially "fixing" the soil when injecting polyurethane foam. The stuff expands rapidly, cures in 15 minutes, comes out as hard as concrete, 3-5 lbs per cubic foot, and is environmentally safe. So you don't have to worry about contaminated soil with this stuff. Polyurethane is so safe that it's applied with pacemakers. Polyurethane foam can relevel structures as small as a home or as large as a commercial business. Mind you, not a lot of lift happens. You'll get maybe an inch or two under the best conditions, but it has that capability nonetheless. Other aspects determine how effective polyurethane is for deep injection. It also depends on the type of foam used. Other factors to consider: How strong is the foam? How deep was it injected? How dense does it go in? It can sometimes come out stronger than concrete. ## How Much Can Polyurethane Foam Carry? It can sometimes get even higher than that depending on the foam and how it's injected. There have been instances where piers were used to lift a building, but it didn't work. Then we brought in semi-trucks full of polyurethane foam that was then injected and able to lift the building. Four to five injection guns had to be used at once to lift the structure. Deep injection with polyurethane foam can sometimes perform miracles when galvanized steel pier underpinnings struggle. The main objective of polyurethane is [[service:soil-stabilization|soil stabilization]], but the stuff can lift. We've lifted a bridge before. It can work. ## Why Carrying Capacity Is Important Again, the primary purpose is to densify the soil. That's incredibly important when it comes to stabilizing your home or business with a slab-on-grade foundation, especially after lifting your home using a galvanized steel push pier and underpinning system. ## Soil Affects the Effectiveness of Polyurethane Foam With highly expansive soil, the foam cannot permeate as well compared to sandy soil. The soil will be pushed out and you'll have blobs of polyurethane foam. You can still fill voids and do stuff with it. When polyurethane foam is injected into the ground, it has nowhere to go. You can have highly expansive soil pushed away while the void is filled with foam. It mixed a little bit with whatever it can, but most of it is being pushed out. ## Polyurethane Foam Can Be Used for Shoring Purposes If we need to excavate, we can create a wall using deep injection with polyurethane foam. If you have two buildings next to each other and one side needs to be looked at, the soil can be densified so the existing building won't be affected by excavating. It helps with new construction. ## Are There Times Deep Injection With Polyurethane Is a Bad Idea? Yes. Soil conditions don't always allow for that. If soil conditions are down further, a galvanized [[solution:foundation-underpinning|steel underpinning system]] would be better. Why? Driving a steel tube into the ground is far easier and better for your wallet. Have a look at how [[solution:polyurethane-foam-injection|polyurethane foam injection under the foundation]] costs depend on the application. ## Learn More About Deep Injection With Polyurethane Foam You've learned about the basics of deep injection with polyurethane, why polyurethane is awesome, the carrying capacity of the stuff, its effectiveness with soil, and the cost per square foot. Take the time to learn more about polyurethane and deep injection. We won't make it a heavy burden for you. We have the article so you can have light work and a solid knowledge of how this stuff works. And learn about [how the deep injection with polyurethane foam process works](/foundation-repair/solutions/polyurethane-foam-injection/). ## Schedule a Free Evaluation Foundation movement is easier to judge in person than from a photo. [Schedule a free evaluation](/contact-us/) and a Dalinghaus specialist will walk the property with you and explain what the evidence shows.