What Are Insulated Concrete Forms?

     Insulated concrete forms (ICFs) are a type of construction building technology that involves stacking foam blocks, pouring concrete into the gaps, and using reinforcing steel to create a strong, energy-efficient, and durable structure. There are numerous benefits to using ICFs in construction projects. First and foremost, ICFs provide excellent insulation, which can help reduce heating and cooling costs by up to 50%. The foam blocks used in ICF construction have a high R-value, meaning they can prevent heat transfer through walls and keep indoor temperatures stable, reducing the need for energy-intensive heating and cooling systems.

​

     ICFs also offer enhanced durability compared to traditional wood frame construction. They are designed to withstand extreme weather events, such as hurricanes, earthquakes, and tornadoes, making them ideal for homes and buildings in areas prone to natural disasters. In addition, the reinforced concrete used in ICF construction makes structures resistant to fire, mold, and pests, ensuring a longer lifespan and lower maintenance costs over time.

​

      ICFs are also an environmentally friendly choice for homeowners. The insulation provided by ICFs helps to reduce the amount of energy needed to heat and cool the home, which in turn reduces the amount of greenhouse gases emitted into the atmosphere. Additionally, the materials used to create ICFs are often made from recycled materials, and the blocks themselves can be recycled at the end of their lifespan. Overall, ICFs offer a range of benefits to homeowners, including energy efficiency, durability, and sustainability, making them an excellent choice for those looking to build or remodel their homes.

​

​

What is ICF? 

Resembling a large Lego block, ICFs are light weight foam blocks made from hypo-allergic, EPS hard foam (expanded polystyrene) that are stacked together to make up the foundation and walls in a building. Once assembled into the desired shape they are filled with concrete making the building strong and energy efficient. The ICF construction technique was first developed in Europe following World War II as an inexpensive and durable way to rebuild damaged structures. The first patent was registered in the early 1940s.  The adoption of ICF construction has steadily increased since the 1970s and today it is one of the most preferred building techniques for the educated consumer.

 

 

Energy Savings

The R-value measures the resistance a material has to heat transfer. The higher the R-value the more insulated your building is and the less energy is needed to maintain a comfortable temperature inside.  Most buildings that are built with wood have insulation placed into the walls between the studs. The insulation values are usually R-13 to R-21 depending on the wall thickness.  

However, true insulation value of wood buildings is usually 15% to 50% below that.  A wood frame wall is made up of several components, not all of which have the same R-value. For instance, 2x6 wood stud has an R-6 value whereas a 2x4 stud is R-4.  When you combine the R-value of the insulation and wood studs the average R-value of the house walls can be as low as R-7.   The wood studs form a “thermal bridge” which allows heat to transfer through the stud.   Those yellow stripes are the heat leaving the building through the wood studs. From a whole-wall perspective, framed walls operate at far lower R-values - sometimes only half of the advertised value.

 

Nudura ICF walls consist of two layers of EPS which provide two continuous barriers of insulation with a combined R-value of 24. The center cavity is filled with concrete forming a solid monolithic structure from the footings to the roof.  From a whole-wall perspective, an ICF wall lives up to the advertised R-values because thermal bridging is absent as seen in the picture to the right.  

​

A drafty house is the biggest source of energy loss.  It accounts for up to 40% of your heating and cooling bills.  In a wood built building, energy escapes through framing of the ceiling, walls and floor.  Wood studs and beams warp, twist and shrink over time causing gaps to increase in size. We all have felt drafts in our wood built homes on very windy days, even seeing the curtains move, but not with an ICF built home.
 

A Nudura ICF building is a draft free because it’s two layers of continuous foam insulation and a solid mass of concrete from the foundation up to the roof prevents air infiltration. No drafts even on the windiest days.   

 

​

​

Healthier Living

Many building products have formaldehyde, asbestos, fiberglass or give off a gas that is harmful to humans and pets.  Conventionally built homes and buildings typically have an indoor air quality 20% more polluted than outside.  A home built with Nudura’s ICFs that have a properly installed air exchanger will offer the most clean indoor environment available, reducing the infiltration of air born allergens. Nudura’s ICFs are made so that they won’t support the growth of mold, mildew or other harmful microorganisms.  Nudura ICF foam is nontoxic, free of formaldehyde, asbestos, fiberglass and will not give off any volatile organic compounds (VOC).

 

Radon is a radioactive cancer-causing gas that is colorless and odorless. According to the US EPA, nearly 1 in 3 homes have levels of the gas that can cause health problems.  Radon penetrates the home through the basement.  A properly installed Nudura ICF foundation and walls will help to prevent leakage of radon gas into the home.

 

Pest proof

Nudura ICFs and concrete are an unappealing food source for termites, carpenter ants or rodents that often dine on or reside in wood-framed walls; and because of the continuous barrier of concrete from the basement up to the roof, insects and mice cannot penetrate and live inside the walls. 

 

Greater Comfort and Quiet

Those who live in a Nudura home say the absence of cold drafts and unwanted noise are the biggest pluses, even topping the energy-saving benefits.  Houses built with Nudura ICFs have more even air temperatures and are not drafty. The barrier formed by the foam-and-concrete sandwich cuts air infiltration by as much as 75% when compared with a typical frame house. The high thermal mass of the concrete also buffers the home's interior from extreme outdoor temperatures, while the continuous layer of foam insulation minimizes temperature fluctuations inside the home by eliminating the cold spots that can occur in frame walls along the studs or at gaps in the insulation. Nudura walls are equally effective at keeping out loud noises. The greater mass of concrete walls can reduce sound penetrating through a wall by more than 80% when compared to stick-built construction. Although some sound will still penetrate the windows, a concrete home is often two-thirds quieter than a wood-frame home. Say goodbye to waking up to loud outside noises such as, thunder, traffic, airplanes, or noisy neighbors. A Nudura wall has a sound transmission coefficient of STC  50+.

 

Security and Safety

Homeowners and builders in hurricane- and tornado-prone areas, including those rebuilding after Hurricane Katrina, are increasingly turning to concrete structural walls to stand up to fierce storms that would otherwise level a wood-frame home.  Tests have shown that ICF walls can withstand flying debris from tornadoes and hurricanes with wind speeds of up to 250 mph. And the Federal Emergency Management Agency (FEMA) recommends ICF construction for building tornado-resistant safe rooms. Nudura walls are bullet-proof.  Now instead of having a safe room, you can have an safe home.

 

Fire Resistant

Concrete is naturally fire-resistant.  Insurance companies recognize concrete as being safer than any other form of construction when fire threatens a home. In fire-wall tests, ICF  concrete walls withstood continuous exposure to intense flames and temperatures of up to 2,000 degrees F for as long as 4 hours without structural failure, compared with wood-frame walls that collapsed in an hour or less.

 

 

Environmental

Energy savings, longevity and use of recycled materials help to make ICF construction a more environmentally friendly choice.  Nudura uses recycled material and is considered a “Green Building Product.”  Building with Nudura can contribute in numerous categories within the LEED Rating system for both commercial and residential. A study published by the Portland Cement Association show that over the life span of a house, ICF has a reduced CO2 burden vs. wood-frame construction, by 220,460 lbs.

 

Longevity

Wood buildings rot, decay, suffer from mold and termite infestation and with time is extremely susceptible to being damaged or destroyed by natural disasters.   Nudura ICF walls use concrete which requires little or no maintenance and stands up to all of nature’s fury.  Your building will last.

 

 

Build in any Season

Due to the fact that an ICF form is insulated, cold weather construction is not hampered by the same limitations or special needs of conventional concrete forming.  After any concrete wall is poured there is a curing process that needs to occur. Without adequate curing conditions the concrete wall weakens and is prone to cracking and even shifting.

 

A common complaint in new homes is leaky basements due to cracked foundation walls.  Using Nudura ICFs, the concrete is protected by ICFs insulation which means that the curing process will complete as required.

In fact, because of its optimum curing environment, a Nudura ICF wall will cure to a stronger hardness than a conventional wall. Rest assured that your Nudura ICF wall will not leak, or crack regardless of what season you build in.