ICF Foundations: What Are They, and What Benefits Do They Bring?

At Tectonic Design + Build, we’re committed to building stronger and healthier homes within the greater Boulder, CO community. We’re also committed to informing you of the ways in which we work to accomplish that goal, which includes the specialized building materials and techniques we use.  There are many types of energy-efficient building materials, and there are many types of fire-resistant construction materials. But if you’re looking for one that checks both of those boxes, you will want to explore insulated concrete form (ICF) foundations for your home.  Let’s talk about ICF foundations — including what they are, and how they can help you build a more efficient, resilient home. 

What Are ICF Foundations? 

Insulated concrete forms, or ICFs, are cast-in-place concrete walls that are sandwiched between two layers of insulation material. They’re created by taking molded expanded polystyrene (EPS) shells that stack together to make foundational forms — think Legos! The forms are then filled with concrete, which makes a strong foundational wall as it solidifies.  ICFs are most often used as a durable, energy-efficient alternative to traditional wood foundations. However, they can also be used to completely replace all of the wood framing within a home — building up the structural wall components. 

3 Main Benefits of ICF Foundations

Although they’re starting to gain more popularity, many homeowners aren’t even aware that ICF foundations exist, which is unfortunate because they come with a long list of benefits in comparison to their traditional wood counterparts. Here are just a few of the main benefits we’ve seen ICF foundations bring homeowners in Boulder, CO and beyond. 

1. ICF Foundations Offer Improved Fire-Resistance

Arguably the most important benefit ICF foundations bring to Boulder, CO homes is that they’re the #1 most fire-resistant building material available.  ICFs have been tested to have a burn rating of 4 (continuous) hours, which is pretty incredible when you compare it to wood framing’s burn rating of just 15 minutes. And, when you take into account that most wildfires blaze past a house in much less than four hours and aren’t usually burning that long, that 4-hour burn rating is often the difference between a house demolished and a house still standing.  We’ve seen it happen first-hand here in Boulder, CO. Homes that were built with ICF foundations were still standing after the wildfires swept through our community last year. And for those families, the effects weren’t as devastating. They were able to keep parts of their homes, if not the entire structures, while their neighbors faced insurmountable loss.  Living in an area that’s at high risk for wildfires, it’s important to build back stronger. ICF foundations provide the ultimate level of protection against future devastation and loss, which is why we advocate for them so strongly here at Tectonic. 

2. ICF Foundations Can Provide High Energy-Efficiency

ICF foundations rank high in energy efficiency for two reasons: they keep an airtight building envelope and they’re amazing heat retainers.  An airtight building envelope contributes to good indoor air quality, significantly reducing the amount of dust, allergen, and smoke pollution. It also helps keep thermal heat inside.  Think about it this way: traditional, uninsulated foundations and walls have an insulation value of R-1, while ICFs have an insulation value of R-25. That’s a huge jump, and it makes all the difference in terms of a home’s comfort, health, and energy usage. Both your body and your wallet will thank you!

3. ICF Foundations Have Incredible Durability

Along with their amazing fire resistance, ICF foundations also provide great benefits in terms of durability. In fact, they’re 10x stronger than traditional foundational or framing materials. Not only can they last for hundreds of years, but they can also withstand various weather conditions or unexpected impacts. They’ve even been known to withstand the harsh effects of hurricanes and tornadoes!  And, yes, there are many other components to a home than just the foundation and structure, many of which can be damaged by devastating storms or natural disasters. However, if ICF foundations are in place, the home will still be structurally sound — meaning its occupants won’t have to start over and build from scratch (a bonus for sustainability and resource efficiency). Using ICF foundations is just one of the many ways you can create a healthier, more resilient home. At Tectonic Design + Build, we’re dedicated to building safe, strong, and long-lasting homes — and we’re here to help you build one of your own in Boulder, CO. To learn more about how we can work together, contact our team online.