Insulating Concrete Forms
Insulating concrete forms are lego block like system for forming concrete to build extremely strong, quiet energy efficient homes or buildings. Most insulating concrete forms also called ICF's comprise of two extruded polystyrene panels with different connections on the ends ranging from twelve or sixteen inches tall connected by polypropolene webs creating a void in which concrete can be poured in the middle. These icfs create different size voids ranging from four inches to twelve inches or more depending on the size of structure needed. Also the webs are on different spacing six and eight inches are the most common. It is our recomendation that they be on six inch centers to avoid wavie like walls. it is also our recomendation that the height of the forms be twelve inches tall to calculate projects easier also according to engineering you can put rebar every twentyfour inches instead of everysixteen inches saving you rebar on each job.
Insulating Concrete Form Benefits
Stregnth Tornado projectile testing
Wind projectile testing on ICF's was done by Texas Tech University. ICF walls were built right along 2X6 wood framed walls. A canon loaded with 2x4 simulated flying debre in a tornado. The 2x4s were launched at speeds 150mph at each wall. The ICF wall astonishing was unpenetrated. You could see a small crack in the concrete where it had hit but that was it. The 2x6 wall showed no stopping the 2x4. it went well through the wall. Different siding was put on various 2x4 walls even the ones with brick only slowed the 2x4 but still went through. ICFs are safe enough from flying projectiles and i would even say close to bullet proof.
Quiet Sound Transmission Control STC testing
STC Sound transmission control is a rating scheme to measure decible travel through various walls, doors, and windows. In number terms the higher the figure the higher rating you get of controlling sound. Average wood framed wall has an STC rating of 33. ICF walls have a STC rating of 55. ICF walls will definately keep cars and neighborhood dogs at bay keeping you more sane and sleep better.
Energy Efficient R-Value testing
ICF walls have great insulating value. There are three key factors why ICF walls perform better then most conventional construction. To start lets look at how R-Value is measured. The test is usally in a controlled enviroment putting the test subject in the middle, a heat source measured in BTU's, and a measurement device on the other side seeing how much BTU's transfer through the wall in a given time. Each insulation product has gone through this process and is given an R-rating or U-value which are recipicals of eachother. U-value used outside of the U.S. The problem is they are done in a control enviroment where there are no wind is taking into an account or changing tempature on the outside of your wall system. These are also known as air infiltration and saturation of your insulation.
So for our purposes first R-Value of the ICF according to the test. The five inches of foam in the ICF are about 4.5 R-Value per inch giving ICFs a total R-value of 20-22.
Second ICF's control air infiltration or air leakage of the walls much better. Typical wood framed walls have a complete air turnover of new air to the old air once every two hours. ICF walls have a turnover rate of every eight hours. Air is the fastest way to transfer tempature between a barrier.
Finally thermal mass which is how long it takes to change the tempature of the wall. It could also be described as how fast a wall becomes saturated where one BTU of energy goes into the wall and one BTU of energy goes through the wall. This is important in how effective ICF walls perform better then typical wall. The average wood wall become saturated in a few hours on a super HOT or COLD day. The rest of the night or day your HVAC system fights back to regain saturation control of the wall. Often on these extreme days you notice the radiant heat coming through your walls giving you uncomfort. The average ICF walls takes over nineteen hours before becoming saturated. IF you live in canada the thermal mass attribute of real world effective R-value is less as well as living in mexico. But living in the middle of United States The Effective R-value takes greater effect of thermal mass benefit of Effective R-value.
After these three key factors of Effective R-Value ICFs effective R-value is anywhere from R-40-R52 signficantly greater then typical wood walls with controlled enviroment R-value of R-17to R19 and have no air infiltration or thermal mass benefit. Which actually hinder even the tested R-value.
Fire rating testing
Fire testing on ICF's is an instense process. They build an ICF wall put 5,000 pounds per lineal foot of pressure and maintained for the duration on all four sides. One side of the wall is like a furnace where the tempatures reach 327 degrees F. Twelve probes measure surfaced tempature and ten thermocouples were installed on outside. After four hours of intense testing the wall is immediatly cooled and inspected. The outside highest tempature that was reached 140 degrees F well below the 327 degrees. The rating on the ICF passed servering four hour fire wall rating but could of gone longer without failing they were just concerned with the higher end requirments of commercial buildings. Where wood walls are only one hour before the wall will fail and collapse on you.
Moisture barrier testing
Mold growth testing