ICFs offer all the benefits that have made concrete the material of choice for construction worldwide. They provide solid, high strength walls that resist the ravages of fire, wind and Father Time.
But ICF's also do plain concrete one better – or rather, two better – by giving two built-in layers of foam insulation. ICF construction takes the three-step process of framing, insulating, and wrapping a structure, and ties it all into one. Forms are constructed from expanded polystyrene foam and stacked like building blocks to form the exterior walls of a building; then the forms are reinforced with steel and filled with concrete. The forms interlock and fasten one to the other to provide a seamless "foundation to rafter" fully insulated, reinforced concrete walls. ICF's stay in place as a permanent part of the wall assembly.
This gives an ICF structure some sizable advantages over other construction techniques. Home and building owners can enjoy greater energy efficiency, more peace and quiet, and enhanced day-to-day comfort. All of this is wrapped up in a solid, high-quality building package with an utterly remarkable feel.
Contact a County Materials' sales representative for more detailed information on ICF Construction, and what products are available in your area.
Energy savings and comfort are built into every Insulating Concrete Form system. Because of the triple insulative nature of these forms, ICFs are extremely energy efficient. The R-value of the insulation, coupled with the thermal mass of the concrete, and the elimination of air leakage, typically makes for an R-30 energy rating or higher. Exterior walls on wood framed homes typically have an R-value of 20 or so.
But that’s not all! On the comfort side, an ICF home provides temperature stability, without the highs and lows of traditional stick-framed housing. Air infiltration in an ICF Home is minimal due to the continuous air barriers provided by the foam insulation and the concrete. Likewise, there are no convection currents within wall cavities.
The concrete walls of an ICF home have high thermal mass, which buffers the interior of a home from the extremes of outdoor temperature during every 24-hour cycle. This reduces both peak and total heating and cooling loads.
This combination of high R-values, low air infiltration, and high thermal mass is believed to account for the amazing 25% to 50% energy savings of ICF versus wood or steel-framed homes.
New ICF homeowners almost always remark on how unbelievably quiet their new house is, compared with their old stick-build home. They expect the new-found comfort and energy efficiency, but the peace and quiet – the protection from outside noise – never fails to surprise and delight them.
In sound transmission tests, ICF walls allowed less than one-third as much sound to pass through as do ordinary frame walls filled with fiberglass. With double-glazed windows in ICF walls and beefed-up roof insulation, you will rarely hear street noises or airport traffic.
The high-mass walls of an ICF home not only give it a remarkably solid feel, but they also make it safer for the family. And this makes it a remarkably solid and secure investment, too. Concrete homes have a proven track record of withstanding the ravages of hurricanes, tornadoes and fires, when all the stick-build houses around them are in ruins. In Tornado Alley, homes built with a continuous structure, tied down through the foundation, are favored for high wind resistance. Insulated concrete forms are often used for the construction of safe rooms in these high-wind areas because of their resistance to strong wind and wind-borne debris.
In firewall tests, ICF's stood exposure to intense flame without structural failure longer than did common frame walls. The polystyrene foam used in most ICF forms is treated so it will not support combustion. Also, tests show that its tendency to transmit an outside flame source is less than that of most wood products. Many insurance carriers are offering a premium reduction on a homeowner’s policy for an ICF home.
With ICF homes, the equation is simple. No Rot = Less Repair and Maintenance. Neither polystyrene nor concrete will ever rot or rust. Concrete can even be exposed to the elements for centuries with few ill effects. Reinforcing steel, buried deep inside and protected by concrete’s alkalinity, does not corrode.
Building with ICFs is healthier for the environment in a number of ways: by minimizing the number of different building products involved in construction, by reducing the amount of waste generated on the construction site, and by lowering energy requirements for heating and cooling.
ICF homes provide a healthy indoor environment, too. Nothing held within or ordinarily emitted by an ICF wall is toxic. The measurement of the air contents of actual ICF houses shows an almost complete absence of any emissions.
ICF homes can be designed in any style, and will accept any traditional exterior finish including vinyl or wood siding, stucco and brick. Because custom angles and curves are easily created, it’s simple to build in bows, bays and radiuses. And ICF systems accommodate any of today’s most popular design features, such as tall walls, large openings, long floor spans and cathedral ceilings. Window and door openings of any size are possible.
Cutting block is simple in ICF construction so, unlike the cumbersome concrete constructions of the past, custom window designs and complex angles are commonplace. When considering building with ICF's, be sure to discuss how to accommodate the doors and windows with your contractor. With ICF's, windows and doors must be cut and blocked before the concrete is poured. Blocking the openings accomplishes two things: it holds back the concrete to preserve the opening, and creates the frames for the doors and windows. Once a crew is experienced in ICF construction, scheduling and speed become key benefits. An experienced crew can put up a house faster with ICF's than with traditional framing.
Originally developed in Europe (where concrete home building is standard) ICF systems have been used successfully around the world for more than 30 years. Thousands of ICF homes have been built in recent years throughout the United States and Canada. They have proven successful in every region and climate, from Orlando to Calgary. ICF systems are accepted by all the major model codes in the U.S., and by the R-2000 program in Canada.
Although it looks new and different, anyone with construction experience can quickly get up to speed with ICF's. An ideal crew has a mix of concrete placement and carpentry experience. Once the crew has some practice, each ICF-build home requires less skilled labor and less total labor than a wood-framed home. And ICF's are very lightweight, so crews stay fresh through the day.
Likewise, ICF's present no problem for the sub-contractors who come after the walls are poured. Since holes, chases and rectangles are easily cut into ICF's with a knife or saw, installation of mechanical systems is a snap. The fastening of drywall and lap siding is just as fast and easy. And mid-course corrections, such as moving an opening, are no big deal – just saw it out and re-form. It’s not more difficult to make changes to an ICF wall – it’s just different.
Over the last ten years, concrete prices have been remarkably stable. Recent price increases in other materials have generated interest in concrete building systems as never before. Labor savings and readily available materials make ICF's, feature for feature, one of the most cost competitive wall systems in the U.S. and Canadian housing markets.
Note: It is strongly recommended that anyone building a structure with ICFs receive the proper training and consultation before starting any project.
For the Walls -
For Lintel Openings -
Our form supplier is the only in-house manufacturer of ICF forms in the industry. This allows them to maintain strict quality control standards. The brackets are the toughest on the market, made of regrind polypropylene, which eliminates the thermal bridging and corrosion concerns. The brackets are molded 1/2" below the surface of the block eliminating any shadowing concerns when finishing with Stucco or EIFS products on the exterior of the building. In addition, the brackets run the full height of the forms, and the bracket is a full 2.5" wide which is unique in the industry, making it much easier to attach both external and internal wall products.
County Materials sales representatives can help you with your estimate for ICF forms, concrete, and accessories you will need for your project.
It is recommended that an ICF wall be poured one story at a time, no higher than 12 feet. The pour rate should not exceed 4 feet per lift. ICF forms are used for both single and multi-story residential and commercial projects.
With 2.5 inches of EPS foam on each side of the form, an ICF form itself has an R-value of 23. With concrete in the forms, a structure can achieve an R-value of R-28 to R-32 using Thermographic Testing.
County Materials' ICF forms come with a full 2.5" bracket located every 8" on center. This makes it easy to attach any type of wall covering, including EIFS, stucco, siding or ties for brick or stone veneers. The interior walls will easily accept sheet rock screws for attaching standard sheetrock.
The amount of rebar is determined by the design of the building. County Materials sales representatives can help with determining how much rebar will be needed for your specific project (in accordance with local codes and engineering specifications only).
LEED® stands for Leadership in Energy and Environmental Design. It is a green building rating system developed by the U.S. Green Building Council (USGBC). The purpose of LEED is to promote buildings that are environmentally responsible, profitable and healthy places to live and work. The LEED system was developed for designing, constructing and certifying the greenest and best buildings possible. ICF’s and concrete can help a project achieve certain LEED credits in specific categories. Consult with a County Materials sales representative for info on LEED points.
YES. With traditional stick building, moisture can become trapped within the open cavity of a wood stud wall causing, mold, mildew and rot problems. Since ICFs are closed cavity construction, there is no place for moisture to accumulate. In addition, EPS foam, rebar and concrete are resistant to mold and mildew.
YES. Most contractors have the ability to create openings in ICF walls using concrete cutting tools that are available at many rental centers.
YES. Every major code body in North America, including ICC and CCMC, has approved ICFs.
ICF walls have a sound transmission classification of STC 48, which is twice as high as a wood-framed wall. Structures built with ICFs provide a quiet, comfortable interior.
Just like wood frame construction, local building codes do require methods for protecting foam below-grade in high termite areas. However, ICF’s do not provide any food value for insects or rodents and termites cannot affect the structural integrity of an ICF wall because it is filled with concrete.
Some states have a code that requires a vapor barrier no matter what type of construction is used. ICFs, however, provide a natural barrier against air and moisture because of the concrete and two layers of foam.
YES. ICF structures are up to 8 1/2 times stronger than wood framed structures. The standard wall design can withstand winds greater than 160 m.p.h. and do not support combustion, making them highly resistant to severe weather and fire.
A wooden, steel or vinyl buck is built and incorporated into the ICF wall prior to pouring concrete. Once the concrete has cured, doors and windows can be installed.
YES. As with any below-grade construction, the industry recommends waterproofing no matter what kind of soil or grade is present for your project. Ask a County Materials' sales representative for available waterproofing products for ICF foundations.
|4 inch ICFs||6 inch ICFs||8 inch ICFs|
Straight Form dimensions:
|48" long, 16" high||48" long, 16" high||48" long, 16" high|
|17" x 33" long, 16" high||21" x 37" long, 16" high||21" x 37" long, 16 high|
|12" x 12" long, 16" high||12" x 12" long, 16" high||12" x 12" long, 16" high|
|Brickledge:||N/A||48" long, 16" high||48" long, 16" high|
|Overall Width with Foam:||9.25"||11"||13"|
|Concrete Volume per Form:||0.07 yards||0.10 yards||0.13 yards|
|R-value for Forms only:||R-23||R-23||R-23|
Supplier of Fox Blocks ICFs: