ICF 101

Components of an ICF Wall

Scroll through the different elements that make up an Insulated Concrete Form assembly.

Insulation

ICF blocks have two sides of expanded polystyrene (EPS) foam that create an air-tight enclosure with continuous interior and exterior insulation.

Webbing

Embedded webs or cross ties within the form hold the two layers of foam together, preventing compression and supporting reinforcement during concrete placement.

Fastening Strips

Nudura ICFs have built-in fastening strips located every 8 inches (203 mm) for securely attaching finish materials like interior drywall and exterior cladding.

Reinforcing Materials

Steel reinforcement, also known as rebar, can be placed vertically and horizontally within the ICF blocks prior to pouring concrete. Also consider fiber-reinforced concrete for additional support.

Alignment Systems

A metal alignment system is temporarily fixed to the inside or outside of the hollow ICF walls to keep them plumb while concrete is being placed.

Concrete

The cavity between the EPS panels is filled with concrete to create solid, monolithic walls with impressive thermal mass and structural stability.

Building with ICFs

Explore the ICF construction process with these 6 steps. For a more detailed and technical walkthrough, join our in-person and online training courses.

See ICF Training Options

Pre-Construction Preparation

Confirm that the footings or slab-on-grade foundation is properly prepared, level and free from debris.

Form Stacking

Insulated Concrete Forms are placed with each new block connecting to the adjacent one. Vertical seams are staggered for optimal strength and stability.

Reinforcement

After stacking each horizontal layer of ICF blocks, steel reinforcements are installed in the cavities, snapping into place in the webbing.

Alignment System

A temporary alignment system is placed at regular intervals along the walls to enable proper alignment during concrete placement.

Concrete Placement

After each story is stacked and reinforced, concrete is placed into the ICFs, filling them completely. The process is repeated, installing floor systems and roof trusses as needed.

Finishing Touches

Windows, doors and other fixtures are installed. The interior finishes, such as drywall, and exterior finishes, such as siding, brick or EIFs, are installed.

ICFs Speed and Simplify Construction

Nudura® Insulated Concrete Forms condense six building elements into one to streamline building construction. Take a look at our 6-in-1 system!

Form System: With straight, curved and corner blocks, Nudura’s concrete forms enable poured foundations and solid concrete walls for any building design and room configuration.
Wall Structure: Once the forms are reinforced and filled with concrete, the structural wall assembly is complete and ready for subsequent building trades.
Insulation: The EPS foam insulation on both sides of the concrete core provides substantial thermal protection to minimize heat transfer through the building envelope.
Air Barrier: An air barrier is built into the Nudura ICF wall assembly due to the permeance levels of the foam insulation, which helps mitigate air leakage.
Vapor Barrier: Your vapor barrier comes as part of the Nudura form system to prevent moisture infiltration and mold in the wall cavity.
Interior and Exterior Finish Anchorage: ICF blocks have embedded fastening strips to easily anchor interior and exterior finishes, like drywall and cladding.

Why Choose ICFs

Why build with ICFs? Check out the benefits of Insulated Concrete Forms and how they enhance both the building process and the quality of the finished structure.

High-Performance Building Envelope

ICFs reduce a structure’s energy consumption by minimizing air leaks, thermal bridging and heat transfer through the walls.

Design Versatility and Aesthetics

Insulated Concrete Forms come in many shapes and sizes for design flexibility. They can also accommodate virtually any exterior finish, including masonry, siding, stucco, EIFS and exterior panels.

Ease of Installation and Time Savings

ICFs are lightweight, easy to stack and can be installed year-round. By speeding up wall construction, subsequent trades can proceed sooner, and tenants can occupy the building sooner.

Indoor Comfort

ICFs boost building comfort by providing soundproofing, improving the indoor air quality, and promoting consistent interior temperatures.

Resistance to Wind and Impact

Even during extreme weather conditions, Nudura ICF wall assemblies can endure winds of up to 250 mph (402 kph) and prevent wind-blown debris from breaching the building exterior.

Fire-Rated

ICFs provide passive fire protection, limiting the spread of flames during a fire. Nudura ICF walls have a fire-rating of 4+ hours, compared to wood-frame walls, which have a 45-minute rating.

ICFs and Sustainable Design

ICFs contribute to the sustainable design of buildings through their increased energy efficiency, longevity, reduced need for lumber and lack of material waste.

Energy Efficiency

ICF walls maintain interior temperatures longer than other construction methods, enabling the structure’s mechanical systems to heat, cool and ventilate the structure more efficiently.

Longevity

ICF buildings are very durable and require less maintenance than traditional building materials, reducing the need for more materials, labor and equipment to repair or replace them.

Reduced Lumber

Using ICFs as opposed to conventional framing methods cuts the amount of wood used and reduces the negative impact on the environment.

Less Waste

Nudura’s reversible ICF block can be flipped in different configurations and trimmed on-site to decrease waste. And any EPS foam or webbing that is not needed can be reused on another project or recycled.

Fewer Shipments

The hinged nature of Nudura ICFs allows the forms to fold flat and stack together tightly, which means you can fit more blocks on the truck to save on freight costs and unnecessary shipments. You’re not shipping air!

Energy Initiatives

Nudura ICFs help buildings reduce their carbon footprint and attain carbon-neutral, zero energy, net-zero or net-positive status. They also contribute to LEED, the Passive House Standard and Living Building Challenge.

Applications

Does ICF Make Sense for You?

See how ICFs benefit everyone throughout the construction process.

Builders and Developers

ICFs buildings are constructed faster and with more durability than traditional methods while meeting or exceeding building codes.

Architects and Engineers

ICFs offer design flexibility with endless aesthetic options to give clients a beautiful and sustainable building.

Homeowners

Owners of ICF structures will experience lower heating and cooling bills with lasting safety and comfort.

Additional Resources

Nudura offers a variety of online resources to support you in your ICF journey, regardless of your role in building design and construction.

Educational Resources

Check out our blog, YouTube channel and training opportunities for the latest ICF educational content!

Blog
YouTube Channel
Training Opportunities

Technical Resources

For more technical data, visit our product pages or see these resources:

Installation Manuals
Pre-Design Criteria
Testing

More on ICF Benefits

To learn more about Insulated Concrete Forms, dive into these product features:

Net-Zero
Disaster Resiliency
ICF vs Other Construction Methods

Explore our Resource Library