Insulated concrete forms are hollow foam blocks used to construct the exterior walls of a building, which are reinforced with rebar and then filled with concrete. Building with insulated concrete forms is lighter, faster, more resilient and often more cost effective than most other forms of building. This building material is rising in popularity for all forms of residential and commercial building, including hospitals, schools, office buildings and private homes for exactly these reasons. As a contractor, have you considered delving into insulated concrete form (ICF) building construction, but don’t know where to start?

The National Ready Mixed Concrete Association (NRMCA) has some upcoming trainings that can help you get started with this new material and technique. The NRMCA is a membership organization for the concrete industry and is a leading industry advocate that provides information and updates to its members about the latest techniques, materials and technologies. This includes professional development courses and trainings.

Professional development is important for any contractor as everyone in the professions needs to stay up to date to keep their crews and worksites safe, efficient and cost effective. The NRMCA is a great resource for trainings on the latest in the concrete industry. Often, these courses also include continuing education credits to count toward receiving professional certifications.

For those interested in ICF construction, including concrete contractors, masonry contractors and wood and steel framers, a coalition within NRMCA called Build with Strength is hosting four ICF contractor training courses across the country to give you an introduction to this growing building material. Attendees can expect an overview of building with ICFs to give them a competitive advantage in today’s construction landscape. The registration fee of each event includes a meal, an ICF training manual, hands-on instruction and a certificate of completion. This particular course also offers four AIA-CES Learning Units and 4 Professional Development Hours (PDH).

ICF Contractor Training Seminars 2

To plan your day, here is a sample itinerary for this half-day training, provided by the NRMCA:

  • 7:30 am: Continental Breakfast
  • 8:00 – 12:00 noon: ICF Contractor Training

Demonstrate the specific characteristics of ICFs

  • Describe the benefits of ICF construction
  • Explain the construction advantages and efficiencies
  • Demonstrate the interaction between trades and ICF installation requirements and techniques
  • Recognize that ICF technology can expand your business opportunities.

The event details are below (click your desired date to be redirected and register with the NRMCA).

November 27, 2018 | Seattle 

December 5, 2018 | Boston

December 6, 2018 | Hartford, CT

January 15, 2019 | Minneapolis

We encourage you to take advantage of these upcoming trainings to begin your knowledge and experience with insulated concrete form construction. This training will increase your competitiveness in the construction market to work with this growing building trend that is lighter, faster, more resilient and more cost effective than other building materials and methods.

ICF Contractor Training Seminars 3

Register online for your local training date and contact the NRMCA for more information on what you can expect and if you have any questions about the training.

Insulated concrete forms (ICF) and structural insulated panels (SIPs) are two common wall systems used to construct commercial buildings and homes. Both wall systems combine structure and insulation into one unit, which quickens construction and reduces labor costs. However, ICF wall systems have several benefits over SIP wall systems.

ICFs, like Fox Blocks, are more energy-efficient and fire-, mold-, and rot-resistant than SIPs. ICFs also have more design flexibility than SIPs. When choosing between SIP and ICF walls, builders and architects should consider the advantages of ICFs, like Fox Blocks, over SIPs wall systems.

What are Structural Insulated Panel Wall Systems?

Structural Insulated Panels (SIPs) Vs. Insulated Concrete Forms (ICFs) 1

(photo by

Structural insulated panels, also called foam-core panels, structural foam panels, stress-skin panels, and sandwich panels, first gained attention 50 years ago for its high level of insulation, air tightness, and strength over wood-framing wall systems. SIPs are 4- and 8-inch thick rigid foam panels, sandwiched between two rigid sheathing materials.

SIP Foam Panels

Extruded polystyrene (EPS), expanded polystyrene (EPS), polyisocyanurate (PIR) polyurethane, or (PUR) are used to make the foam panels for SIPs. With XPS and EPS foam, the foam and sheathing is pressure laminated together. With PIR and PUR, the liquid foam is injected and cured under high pressure.

SIP Sheathing Boards

The most common sheathing boards for SIPS are 7/16 inch thick oriented strand boards (OSB). Other exterior wall sheathing materials include plywood, sheet metal, fiber-cement siding, magnesium-oxide board, fiberglass mat, gypsum sheathing, and composite structural siding panels.  

SIPs create straight walls that are structurally sound, air-sealed, and insulated all in one step. Also, because SIPs are factory assembled, wall construction is quick, which reduces labor costs and construction waste. Roofs, walls, and floors of homes and light commercial buildings can use SIPs. However, there are several problems associated with SIP wall systems.

Disadvantages of SIP Wall System

– Some SIPs, especially those constructed with plywood, OSB, and composite structural siding panels, do not have adequate fire performance ratings.

– Durability problems with SIPs can occur, particularly when using plywood and OSB facings. When plywood or OSB gets wet, the walls may mold, degrade, and rot.

– SIPs have low thermal mass. Materials made of high thermal mass help to stabilize the temperature within a structure, and ultimately save energy and money.  

– Because SIPs are panels, the design of a SIP structure is best coordinated and planned with the panel’s dimensions, without many jogs, bump-outs, or non-90-degree angles. A non-panel friendly design will escalate cos and waste, and diminish the performance of the structure.

Insulated Concrete Form Wall Systems

Structural Insulated Panels (SIPs) Vs. Insulated Concrete Forms (ICFs) 2

Insulated concrete forms (ICFs), like Fox Blocks, are composed of concrete sandwiched between two layers of insulated foam. Above- and below-grade ICF construction creates a disaster-resistant, moisture-resistant, durable, energy-efficient and quiet structure. Also, ICF offers design flexibility and is quick and easy to install.  

The Disaster-Resistant Advantages of Insulated Concrete Foam

ICF Walls are Fire-Resistant. ICF wall construction creates passive fire protection within a building or home by limiting the spread of fire and smoke. If a fire occurs, ICF also hinders the collapse of the structure. Notably, Fox Blocks ICFs have a fire-resistance rating (ASTM E119) of 4 hours for the 6-inch blocks and 2 hours for the 4-inch blocks.

ICF Walls Protect Against Strong Winds and Flying Debris. ICF wall systems, like Fox Blocks, build a strong continuous path that ensures a building can maintain its integrity against winds above 200 mph. Fox Block ICF walls also can resist damage debris flying over 100 mph.

ICFs are Moisture-Resistant

ICF walls, like Fox Blocks, provide a moisture-resistant solid continuous monolithic concrete wall with a perm rating of less than 1.0. The perm rating is a measure of an assembly or a material ability to limit the amount of moisture that passes through the assembly or materials.

The lower the perm rating, the better. Both the 2018 International Building Code (IBC) 1404.2 and the 2018 International Residential Code(IRC) R703.1 do not require an air barrier or a weather- or a water-resistive-barrier on a solid monolithic concrete wall.

ICFs are Healthy and Durable

Structural Insulated Panels (SIPs) Vs. Insulated Concrete Forms (ICFs) 3

ICF wall systems are healthy and durable because they are moisture-resistant and non-organic, which limits the growth of mold and wood rot. Mold and wood rot may occur in the presence of moisture or organic materials, like wood. Mold is unhealthy to those inside the building and wood rot can reduce the structural durability of a building.

ICFs Create a Tight-Building Envelope that is Energy-Efficient

– High-thermal mass ICFs contribute towards a high-performing, energy-efficient building or home. High thermal mass materials absorb and store heat energy. ICF walls then stabilize temperature shifts within the structure by slowing the rate of heat transfer.

– Fox Blocks insulated concrete forms exceed ASHRAE/ANSI 90.1 energy code requirements, and create sustainable buildings with superb moisture resistance and energy performance.

– Fox Blocks also provide continuous insulation with an R-value of 23, which creates an airtight building envelope with better performance than wood- or steel-frame construction.

ICFs Create Quiet Walls

The EPS Industry Alliance (a voice for the ICF industry) reports that about one-quarter to one-eighth as much sound penetrates through an ICF wall compared to a wood-frame wall. Fox Blocks, for example, have a Sound Transmission Class (STC)1 rating of STC 45-50+ and can create a quiet and peaceful interior for a building.

The Design Flexibility of ICF

The strength and flexibility of ICFs allow builders and architects to create any imaginable size or style of a home or building. The ICF forms are easy to cut and shape, including customized architectural effects, such as cathedral ceilings, curved walls, large openings, long ceiling spans, and custom angles.

ICFs are Quick and Easy to Install

Structural Insulated Panels (SIPs) Vs. Insulated Concrete Forms (ICFs) 4

ICFs, like Fox Block Series, is fast and easy to install, which saves time and costs. The Fox Block is an all in one wall system that combines five construction steps into one, including air barrier, structure, insulation, vapor retarder, and attachment. This feature significantly hastens project delivery by eliminating the need to coordinate multiple trades, while accomplishing all of the wall system’s objectives.

Insulated Concrete Form Vs. Structural Insulated Panels Wall Systems

ICF wall systems have several advantages over SIP wall systems.

– ICFs are a high-thermal mass material that is air- and moisture-resistant.

– ICF is more energy-efficient and fire-, mold- and rot-resistant than SIP.

– An additional advantage of ICF over SIP construction is ICF has more design flexibility and can easily accommodate complex architectural curves and contours.

While ICFs create suburb wall systems, they are not suitable for a roof assembly. The pre-insulated, pre-engineered SIPs are ideal for large spans of roofing and will contribute to an energy-efficient and air-tight structure.

Please visit Fox Blocks for more information on insulated concrete foam vs. structural insulated panels.

To protect a building from fire and ensure the safety of its occupants, today’s contractor and architects aim to include fire-resistant components, like Fox Blocks insulated concrete forms (ICF), in their new construction projects. The growing focus in fire-resistant building design is highly due to a rise in wildfires and longer wildfire seasons.

In 2017, there were 31,017 wildfires in the United States; an 8 percent increase over 2016. Many scientists blame the increase in wildfires on increasing global temperatures, early snow melts, and drier forests due to climate change. Protecting a building and its occupants from dangerous fires requires using fire-resistant materials, like Fox Blocks, in new construction projects.

Passive Fire Protection for a Fire-Resistant Building

Fire-Resistant Building 1

Passive fire protection restricts the spread of fire through a structure, which reduces the danger to the occupants and damage to the property. Passive fire protection also protects vital structural components and prevents the collapse of a building. Passive fire protection is often not visible to the occupants; however, when a fire happens, its value in saving lives and protecting property is clear and essential.

Accomplishing passive fire protection is through the use of fire-resistant walls, windows, doors, roofs, and vents.

Fox Blocks Create Fire-Resistant Walls

Fire-Resistant Building 2

A critical element of passive fire protection is the wall system. An excellent option for passive firewall protection is Fox Blocks insulated concrete forms (ICFs). The 6-inch Fox Blocks have an ASTM E119 fire rating of four hours (twice the two-hour requirement), an ASTM E84 reported values for flame speed of less than 25, and smoke development of less than 450.

Along with excellent fire-resistance, Fox Blocks are disaster-resistant, noise reducing, and have high thermal mass with an R-value of 23. Also, because Fox Blocks provide a solid continuous monolithic concrete wall with a perm rating of less than 1.0, Fox Blocks control moisture intrusion and prohibit the growth of mold and mildew. Importantly, Fox Blocks exceeds ASHRAE/ANSI 90.1 energy code requirements, and create energy-efficient buildings.

A best practice for constructing a fire-resistant building includes a fire-resistant wall system, like one constructed with Fox Blocks ICFs.

Windows and Doors for a Fire-Resistant Building

Fire-Resistant Building 3

Fire-resistant glass in the windows and doors is crucial for a fire-resistant building. Classification of fire-resistant glass in doors and windows is according to their insulation and integrity. Insulation is the length of time the glazing product protects the building’s occupants from the heat radiating from a fire. Integrity is the length of time the glazing contains the smoke, fire, and hot flames in a space, so to lessen the spread of the fire. Fire-resistant building design must include fire-resistant glass in the windows and doors.

The Roof for a Fire-Resistant Building

The roof of a fire-resistant building must resist catching fire. Roofs are susceptible to fire from lightning, wildfires, chimney fires, sparks, fireworks, and burning debris. Constructing a roof with fire-resistant materials is a building’s best protection against a roof fire.

Fire-testing exposure of roof systems is in accordance with ASTM E108 or UL 790. Fire-retardant-treated wood roof coverings must also be in accordance with ASTM D2898. The UL 790 establishes three classes of fire-resistant roofing. A best practice for constructing a fire-resistant building uses Class A roofing.

– Class A roof coverings protect against severe fire test exposures and will not slip from a position, or produce flying brands. Class A roof materials include concrete slate, asphalt glass, tiles, clay tiles, and fiber composition shingles.

– Class B roof coverings protect against moderate fire test exposures to the roof deck, will not slip from a position, or produce flying brands. Class B roof materials include shingles and pressure-treated shakes.

– Class C roof coverings protect against light fire test exposures and will not slip from a position or produce flying brands. Class C roofing products include particleboard, plywood, and untreated wood shakes and shingles.

Vents for a Fire-Resistant Building

Fire-Resistant Building 4

Because flames and embers can enter a building through vents, the design of the vents must resist these intrusions. There are several techniques for protecting vents from flying ashes and embers.

– Protect vents in eaves or cornices with baffles to establish a barrier between the vents and the embers.

– Cover the vent openings with 1/8-inch to 1/4-inch metal mesh.

Incorporating fire-resistant elements in new construction is vital to the protection of the building and its occupants. Crucial components of a fire-resistant building include passive fire protection with fire-resistant Fox Block exterior walls, window, door, roofs, and vents.

Please visit Fox Blocks for more information on fire-resistant building design.

To ensure a tornado safe house that best protects the occupants during a tornado event, the Federal Emergency Management Association (FEMA) highly recommends a tornado safe room or shelter, built according to FEMA guidelines.

A residential safe room built with Fox Blocks insulated concrete forms (ICF) meets and exceeds the criteria for a FEMA residential safe room design for a continuous load path and impact resistance. In the event of a dangerous tornado, a safe room built with Fox Blocks ICF can ensure the safety of a home’s occupants.

The Benefits of FEMA Approved Safe Rooms or Storm Shelters

ICF Tornado Safe Rooms 1

Tornado safe rooms are crucial in the United States (U.S.) where an average of 1253 tornadoes occur yearly, creating wind speeds up to 200 mph or more. The impact of tornadoes is catastrophic and kills annually about 60 people, many from flying or falling debris. The majority of tornado fatalities are located either in a mobile or permanent home. Safe rooms are vital to the protection of a home’s occupants during a tornado event.

A further advantage of a safe room is it increases a home’s value. In fact, a report by Professor Kevin Simmons, an economist with Austin College and the Federal Alliance for Safe Homes, found that safe rooms increase a home’s worth by about $4,200, or on average of 3.5 percent.

Designing and building a tornado shelter or safe room, as specified in FEMA P-361 and FEMA P-320, will create a tornado safe house that provides maximum protection to a home’s occupants during a tornado emergency.

Untangling the Guidelines and Standards for Safe Room Design

ICC-500 – The Standard for Design and Construction of Safe Rooms

The ICC-500 is the International Code Council’s and the National Storm Shelter Association’s (NSSA) standard (ICC/NSSA) for the construction and design of storm shelters (safe rooms). The 2014 ICC-500 is the current ICC/NSSA standard for construction and design of residential and community storm shelters.

ICC-500 – The Referenced Standard for Building Safe Room Used by the IBC, IRC, and FEMA

Since 2009, the International Building Code (IBC, Section 423) and the International Residential Code (IRC, Section R323) have utilized the ICC-500 as their reference standard for building storm shelters. FEMA also uses ICC-500 as a referenced standard for building safe rooms and storm shelters. However, the FEMA guidelines are considered more conservative than the IBC and IRC requirements.

Builders and architects of safe rooms can find the FEMA guidelines in FEMA P-320 (Taking Shelter from the Storm: Building a Safe Room for Your Home or Small Business) and FEMA P-361 (Safe Rooms for Tornadoes and Hurricanes: Guidance for Community and Residential Safe Rooms).  

The ICC-500 is the reference standard used by the IBC, IRC, and FEMA for the design and construction of safe rooms. Residential safe rooms designed to FEMA guidelines provide occupants of small businesses or homes the best safety against high winds and flying debris during a tornado event.

Building a Tornado Safe House with a FEMA Safe Room

A residential safe room is a solid space designed to meet FEMA specifications. A FEMA safe room provides the occupants of a home or small business near-total protection in severe weather events, including tornadoes. T

The construction and design of a residential safe room must follow the guidelines described in FEMA P-320 and FEMA 361. Critical components of a FEMA residential safe room are a strong continuous load path, and resistance to windborne debris, overturning, and uplift.

A Continuous Load Path is Key to a Residential Safe Room Design

ICF Tornado Safe Rooms 2

A strong continuous load path is key to holding the roof, walls, and foundation of a safe room together during a powerful wind event. A continuous load path ensures that when wind loads attack the roof, the loads will transfer to the shear walls.

The shear walls of the safe room are the essential elements of the continuous load path that block the lateral-loads (horizontal wind forces). The walls must keep their integrity and have the strength to support the roof, while concurrently moving the loads to the foundation. Ultimately, the wind loads must move from the foundation to the ground.

A superb product for a residential safe room is Fox Blocks, which are FEMA approved. Fox Blocks reinforced concrete walls have the continuous load path required to resist severe wind events during tornadoes. The Fox Blocks Wall System is also durable and has the strength to support a roof.

Residential Safe Rooms Must Protect Against Flying Debris

ICF Tornado Safe Rooms 3

The walls, roof, and doors of a residential safe room must resist the impact and penetration of flying debris during a tornado.

– A safe room roof must withstand the impact of a 15-pound 2-inch X 4-inch shot at 67 mph.

– Safe room doors should have documented proof that they are compliant with the most current version of FEMA P-361 and FEMA P-320 or the ICC 500 for tornado wind speed of 250 mph.

– Safe room walls must resist the impact of a 15-pound 2-inch X 4-inch shot at 100 mph

The whole envelope of a residential safe room must protect the shelter’s occupants from flying debris during a dangerous tornado.

An ideal choice for a FEMA safe room is insulated concrete form (ICF) Fox Blocks. Fox Block walls resist damage from flying debris traveling over 100 mph. Fox Blocks are the best protection from windblown debris to occupants in a safe room during a tornado event.  

Safe Rooms Must Resists Uplift and Overturning

It is essential to a residential safe room to anchor its foundation so to resist overturning and uplift as it receives the wind loads from of the walls. The anchoring and design of the slab-on-grade foundation must follow the guidelines in FEMA P-361, as defined by the ICC-500 (Section 308.1.1.2). During life-threatening wind events, the foundation of a residential safe room must resist uplift, overturning, and sliding forces.

When designed and built according to FEMA guidelines, a tornado safe room or shelter, for a home or small business, will create a space for the occupants that provides maximum protection during tornadoes. A residential safe room constructed with Fox Blocks meets and exceeds the criteria for a FEMA residential safe room design for a continuous load path and impact resistance.

Please visit Fox Blocks for more information on building a safe room for a tornado safe house.

Modern insulated concrete form (ICF) homes create energy-efficient, disaster-resistant, and durable houses. ICF homes are also low maintenance, quiet, and healthy. Importantly, ICF accommodates all affordability levels, from modern luxury estates to stylish starter homes.

Building a modern ICF home provides homeowners, of all income levels, an energy-efficient, disaster-resistant, durable and healthy house.  

Why Build a Modern ICF Home?

Modern Home Insulated Concrete Form 1

A modern ICF home, like one built with Fox Blocks, is a wise choice for today’s safety- and energy-aware families.

– ICF homes are fire-resistant  

– ICF homes are impact-resistant and can stand up to severe storm events with wind speeds up to 250 mph

– ICF construction is energy-efficient

– ICF homes are quiet

– ICF construction is moisture-resistant and therefore low maintenance, healthy, and achieve a lifespan that is hundreds of years longer than traditional building methods

Specifically, ICF homeowners can expect the following advantages over a wood-frame house: 20 percent or more energy savings, 10-30 percent less outside air infiltration, twice the strength, a 4-hour fire rating, and three times quieter. Building a modern ICF home saves money and energy, and improves the safety and comfort of its occupants.

Design Features of a Modern ICF Home

Modern Home Insulated Concrete Form 2

An essential element of modern home design, as opposed to traditional home design, is the use of newer building materials and technologies, like ICF. Modern ICF homes often include large geometrical patterns and shapes, industrial materials, and sleek lines. The smooth finish of concrete with its subtle shades of gray and functional character further achieve a contemporary look. However, all finishes are available to the exterior of an ICF home: siding, brick, stone, etc. The look of a modern ICF home can vary from sleek and bold to functional and industrial.

Modern ICF House Plans

Because of concrete’s strength and flexibility, ICFs can accommodate most any size or style of a house plan a homeowner can dream up. The ICF forms are simple to cut and shape and may include customized architectural effects, such as curved walls, large openings, long ceiling spans, custom angles, and cathedral ceilings. Common features of a modern ICF house plan include tall and large windows, open floor designs, asymmetrical shapes with unique angles, and flat, multilevel rooflines.

Easy Conversion of Stick Built Home Plan to ICF Home Plan

Furthermore, almost any conventional stick built home plan can be converted to ICF construction either by a builder, architect, or designer. Once built, ICF houses are nearly identical in outside appearance to their wood-framed equivalent. However, there are several slight hidden differences between ICF and wood-frame construction.

1. ICF exterior walls are thicker than wood-frame exterior walls. Therefore, when converting a wood-frame home plan to an ICF home plan, keep the interior dimensions, so as not to lose living space.

2. The overall increase in the dimensions of an ICF home will also require increases in the roof and foundation systems.

Fox Block Modern ICF Homes

Fox Block is a division of Airlite Plastics Company and one of the earliest molders to design and manufacture ICF Blocks. Fox Blocks are insulated concrete forms that reduce construction time and create a modern, energy-efficient, durable, healthy, and comfortable home.  

6 Modern ICF Homes Built With Fox Block

Take a look at these 6 homes built with Fox Blocks ICF forms for inspiration on your future dream house.


Modern Home Insulated Concrete Form 3

A 10,000 square foot modern ICF home designed to minimize energy use and protect the house and its occupants from the threat of hurricanes, common along the Chesapeake Bay.


Modern Home Insulated Concrete Form 4

A 2,250 square foot net-zero, modern ICF home with a complex-hip roof and classic design. The Fox Block construction of this aesthetically pleasing house will also protect the home and its occupants from hurricanes, common along the East Coast.


Modern Home Insulated Concrete Form 5

A 5,200 square foot custom built ICF home blends the appeal of classic craftsmanship with ICF efficiency. The home includes nine levels, a six-point intersect roofline, and an ICF/timber frame hybrid structural system.


Modern Home Insulated Concrete Form 4

A 2,600 square foot ICF traditionally styled home located near the Alabama Gulf Coast.  With the help of Fox Block construction, this home meets the standards for Fortified for Safer Living certification (FFSL).


Modern Home Insulated Concrete Form 7

A 2,700 square foot ICF custom home designed to meet the Town of Old Greenwich, Connecticut historical design requirements.


Modern Home Insulated Concrete Form 8

A 6000 square foot visually unique ICF home with multiple bays. The home also features 7 corners with 45 degrees Fox Blocks and 29 corners with 90 degrees Fox Blocks.

Homeowners from British Columbia to Alabama Gulf Coast have used Fox Blocks to build their new modern ICF homes. For more information on building Fox Blocks contact an expert today.

Project Estimator

Do you want to use Fox Blocks for a project?

Copyright ©2018 Airlite Plastics Company & Fox Blocks. All Rights Reserved. Developed by ICFBase ICF Base