What is ICF?

Nudura Standard ICF

Insulated Concrete Forms (ICF) takes a unique approach to the construction of exterior walls and foundation. According to the online encyclopedia Wikipedia, Insulated Concrete Forms are “stay-in-place formwork for energy-efficient, cast-in-place (reinforced) concrete walls.” By combining the strength of a poured-in-place concrete wall with the outstanding insulation capabilities of high-density foam, the homeowner is given a truly unique home.

Why is ICF superior to standard construction?

Homes that are built using ICF have been found to save up to 44% per year on utilities. A research project was recently completed that revealed that a 5,000 square foot home in East Tennessee incurred a yearly utility cost of just $1,250.00. This home was built from the footers to the roof trusses with ICF and had all electric utilities. This type of construction provides superior energy-efficiency that will keep paying for itself year-after-year.

Another major benefit to building with ICF is strength. Concrete homes have long been regarded as some of the safest homes anyone can choose. Tests have proven that ICF homes provide superior strength in high-wind situations. ICF homes have been proven to withstand up to 250mph winds, or an F4 Tornado. One of the best tests any ICF home has been through was a real-life application in Stoughton, Wisconsin. The ICF home in this situation was one of four being built. One night, a horrific storm blew across the town. During the night, an F3 tornado touched down in the newly established community destroying everything in its path. Three of the four houses were totally destroyed, the fourth home was built using ICF, the other three homes were traditionally built using wood framing. Aside from the windows needing replacement, and the roof needing some repair, the workers were able to return to work later that week and restart construction where they left off.

Noise comfort is another plus that comes with building with ICF. With a sound transmission class rating of 50, the foam insulation provides an excellent noise barrier. In fact, a home in the Knoxville area was a classic example of the level of comfort that comes with ICF. In an upscale community in West Knoxville, a couple was hosting a dinner party with other guests from the community. At the same time every evening, a train passed behind the community creating noticeable noise. When the time for the train arrived, the guests were astonished when they could not hear the train from inside the home.

As you can see, choosing ICF can make a dramatic difference in the quality of life you and your family can have. ICF’s provide many other benefits also including mold and pest resistance, resistance to allergens, quick construction, fire-resistance, and environmental friendliness. If you would like more information about ICF or our company, visit our contact page and feel free to use any of the methods to contact us.

How much does ICF cost?

In order to compare a concrete home to a traditional home, you cannot just compare building costs. While upfront, you can expect to see about a 4% increase in price, when you take the other costs into consideration, homes built with insulated concrete forms are surprisingly affordable. The table below breaks down the total costs in order to see the details of the savings, and when everything is considered, the monthly payment for a concrete home is only $1 more than a conventional home!

  Standard Home ICF Home  
Purchase Price $200,000 $208,000 4% More
Interest $1119 $1163 7.5% Interest
Taxes $300 $312 .15% Tax Rate
Insurance $60 $48 20% Lower
Energy $145 $102 30% Lower
Housing Cost $1624 $1625 Only $1 More!

Technical Specifications

General Specifications (NUDURA):

Flame Ignition Resistance

  • Flash Ignition Temperature of 698*F (370*F) and self ignition Temperature of 806*F (430*C) in accordance with ASTM D1929.
  • A fire retardant is added to NUDURA’s EPS products during manufacturing.

Fire Resistance

  • 6″ (150mm) concrete core provides a fire resistance rating of 3 hours.

Energy Efficiency

  • Thermal resistance of R22 (RSI 3.89) (6″ [150mm] form unit).
  • Thermal performance of an assembled wall can be double that of a typical wood framed wall, depending on certain climatic conditions.

Sound Transmission

  • 6″ (150mm) concrete core provides a Sound Transmission Class of 50.

Water Vapor Transmission

  • Maximum water permeance rating of 3.50 perms-in (200ng/Pa.s.m2/25mm)
  • Tested average based on total EPS:1.68 perms-in (96ng/Pa.s.m2/25mm)

Structural Design Considerations

  • Wall design principle is a monolithic structural concrete wall.
  • Designed as reinforced concrete in accordance with all applicable US prescriptive tables per IRC, SBC, Florida building code, PCA/NHAB EB118 or engineered design as per CAN/CSA A23.3 (Canada) or ACI 318 (USA).

Finishing Requirements

  • Waterproofing/damp proofing and drainage as required by building code compatible with EPS.
  • Interior face of NUDURA wall should be protected with an approved thermal barrier (typically minimum ½” [12.7mm] GWB) as required by building code.
  • Designed as reinforced concrete in accordance with all applicable US prescriptive tables per IRC, SBC, Florida building code, PCA/NHAB EB118 or engineered design as per CAN/CSA A23.3 (Canada) or ACI 318 (USA).
  • Exterior of NUDURA wall should be protected with conventional exterior finish materials such as siding, brick, stucco, etc.

Code Compliance

  • Wall design in accordance with NES, ICBOES, SBCCI PST & ESI code agencies (USA) and National Building Code (CDN).
  • CCMC File # 9420/03131

Example (typical) ICF technical specifications:

Other specifications can be obtained from the following ICF system providers:

Disclaimer: The information on ICF systems, products & materials presented herein is provided for informational purposes only. The links, technical specifications, descriptions, and details expressed do not constitute a specific endorsement of a particular manufacturer. They are provided merely as guidelines and you are urged to select a product line that best meets your design needs.