Call Bob Moore Construction at 817-640-1200  

LEED Construction

Promoting LEED-Certified and Green Building Construction Companies

Bob Moore Construction logo       
Brought to you by Bob Moore Construction and General   
 LEED Construction Articles
 The Challenges of Infill
 Development to Deliver a Gold
 LEED for Core & Shell Project
 The LEED Rating System and
 U.S. Green Building Council
 The Rise In Green Building
 Trends Today
 Construction & Demolition Waste
 - Recycling in the Trenches
 Exploding the Myths of Insulating
 Concrete Form (ICF)
 Construction Technology
 Going Green with Construction
 - Insulation

 LEED Construction

LEED Construction News
KDC Real Estate Development Selects Adolfson & Peterson Construction to Build Raytheon Corporate Campus at CityLine
Maker of Silk Soy Milk Earns LEED Certification for Dallas Beverage Plant
The battle over “green” plastics continues in the building & construction industry
DIRECTV Headquarters Meets Highest Green Building Standards
Kelowna General Hospital buildings earn top environmental certification
WhiteWave Foods Opens Company’s First Certified Green Manufacturing Plant
Latista Closes Deal to Become the Field Management Solution for the Moscow BSA Luzhniki Stadium for the 2018 FIFA ...
2 Central AR Library System Branches Awarded for Going Green
Textura Corporation Named One of the Constructech 50
Architects lead green revolution

 LEED Construction Company > LEED Construction Articles > Exploding the Myths of Insulating Concrete Form (ICF) Construction Technology

LEED Construction Company Articles

Exploding the Myths of Insulating Concrete Form (ICF) Construction Technology

By Eric Williams

The insulating concrete forms (ICF) industry is rampant with inaccurate information. Some have been passed along by industry members, while others represent simple misunderstandings about the technology. Most of these misstatements are made by persons that simply lack the appropriate knowledge behind the information. The toughest part of researching ICFs is not finding the information, but sorting through all of the inaccurate information.

Virtually every aspect of the ICF industry is affected by misstated information, but the most common issues involve discussions of R-Value, waterproofing, and termites and bugs. R-value statements range from R-18 to R-50+. To explode this myth and get a clearer understanding of this myth, you will need a firm understanding of R-value and the difference between PERFORMANCE and TRUE R-values.

Myth 1: R-Value

An R-value is the measure of resistance (R) of heat flow. Heat flow can be resisted by insulating materials such as plastic foams or mineral fibers, or can be slowed by massive dense materials such as thick masonry or concrete. The larger the R-value, the greater the resistance and the better the insulating value.

All building materials transfer heat to some degree. Heat transfer can be measured by any of the following: 1. Conductivity (k); 2. Conductance (c); 3. Transmittance (U); 4. Resistance (R).

The ability of dense materials to retard heat flow depends on their ability to store heat and is measured by specific heat and heat capacity. (BTU per lb. Per degree F; Density lb. Per cu.ft.; Heat Capacity BTU per cu.ft. per degree F)

When it comes to stating R-values in residential construction, the insulation values applied to a wall or ceiling typically refer to the R-value of the insulation material that is installed, not of the wall or ceiling assembly. For example, when a 2x4 stud wall is insulated with R-11 batt type insulation, the builder states that the wall is an R-11. This is not totally accurate and is NOT TRUE since approximately 20% of the wall is not insulated at all. The wood framing and sheathing do have an R-value, but for the sake of making insulation claims, they add very little. The real R-value or PERFORMANCE R-value ends up between R-3 and R-9. Add to this, the fact that the wall is full of penetrations, such as electrical outlets etc. and the fact that the wall itself is basically hollow in nature. This added thought leads to another discussion on air leakage through the wall.

With ICF technology, the TRUE insulation value of the wall is that of the Expanded Polystyrene (EPS) since the EPS provides a continuous insulation plane from the footing to the top plate. The insulation value of the EPS is determined by the density and thickness of the material. Some ICF systems have EPS that is of differing thickness (waffle and post and beam systems) that typically average the thickness of the foam. This is, in my opinion, not an accurate measurement since a bucket with a hole in the bottom doesn’t carry as much water as a solid bucket with a hole at the top. Most ICFs utilize EPS foam that has a density of approximately 1.5 lbs pcf to 2.0 lbs pcf. The insulation values differ only slightly in that range and depending on the testing laboratory, provide R-values between R-4 and R-4.5 per inch of EPS thickness.

The claim that ICF walls are an R-50 started a few years ago after the Insulating Concrete Form Association (ICFA) and several members commissioned CTL Laboratories in Chicago to perform some R-value testing and analysis. The summary of the report basically said that depending on the climate zone, the PERFORMANCE R-values for ICF technology is as high as an R-52 when COMPARED to typical wood frame and batt construction. In order to make the comparison correct, one must ensure that the comparison is being done vs. the alternative to ICF on the particular project. On average, the performance R-value is much less than the claimed R-50. Research by the consumer must be done to clarify the comparison for the actual project. In short, ICF will PERFORM at an R-50, but that statement is not accurate as far as an insulation value goes.

For more information on insulation values, green building, and energy efficient building, try these websites for research: Energy Star Program, Concrete Homes. Do a Google search to find others many others. It is worth noting that there are many options for research on the internet and that I neither own nor control any of the suggested research links listed in this article.

Myth 2: Waterproofing

Yes, below grade concrete construction should always be waterproofed and this includes ICF technology. Three options include: dimpled membrane, peel and stick membrane, and roll-on/spray-on products. In some jurisdictions in the US, a combination of dimpled membrane and peel and stick membrane or roll-on/spray-on products must be used to meet local building codes. It is best to consult your local building code officials and your local ICF supplier to ensure that you meet the minimum code requirements and use only products that are compatible with EPS.

Myth 3: Termites and Bugs

According to the ICFA, the International Residential Code has provisions in the IRC to allow for foam to be used below-grade. The IRC stipulates in addition to chemical soil treatment, foam can be used below-grade on the exterior of the wall if one of the following requirements is met:

  1. All interior partition walls and roof trusses are built of a non-combustible material such as steel studs or pressure treated lumber.
  2. An approved method for protecting the foam plastic and structure is used.

Polyguard Underseal™ XT Waterproofing Membranes has an evaluation report that shows they are an approved method for protecting foam from termites below-grade. Checkout the Polyguard website for additional Polyguard information. Tip, you may want to install an aluminum termination bar along the top edge (AKA: termite stop-ant stop). One benefit, besides stopping insects, is that the termination bar helps out with screeding stucco, etc. over the foam which you will need to protect the exposed area of foam. Also, don’t run your siding down to the grade. This is just another shortcut for ants, termites, and other insects to get up the wall and start nesting behind your siding.

Remember, these insects don’t eat the foam, but they can burrow through it, especially in search of food. Eliminate the food source and eliminate the problem. Wood products can be totally replaced in your new home. There is no longer any reason to use wood products in areas of the US with high termite infestation. Consider steel framing, AZEK Trimboards and V-Buck for your next project and get the wood out! Although many additional myths exist and continue to thrive, it is important that you remain diligent in your information gathering. As you seek additional information, be sure to work with those that have the heart of a teacher. Seek those that have a passion for the industry and both understand and can explain the issues.

Eric Williams is the founder of the Get Ready to Win Network. Contact Eric at or 928-255-5379. For more information about Eric, click here:

Article Source:

About the Author

Zack Verde is with - providing information on green construction.

Article Source:

Bob Moore Construction Company logo

Bob Moore Construction

This website was created to promote green building, LEED construction companies and LEED certification by Bob Moore Construction Company. Bob Moore Construction is a member of the U.S. Green Building Council (USGBC) and the first Platinum Level member of the USGBC north Texas chapter. The company is also a member of AGC, Tilt-up Concrete Association, and the OSHA Local Partnership Program. For more information about Bob Moore Construction visit



LEED Construction
LEED Construction

© 2008-2009 LEED Construction