Insulation for the Building Envelope
Previously, the idea of a jacket was brought up as an analogy to describe the building envelope. Specifically, the notion of an air barrier preventing wind from whisking away heat and affecting occupancy comfort was used. And while you always do want to have a proper, un-compromised air barrier in a building, it’s not the end-all, be-all element. In fact, it’s just one piece of the envelope puzzle.
Having just an air barrier in an envelope in 20 degree weather would be like walking around with just a wind breaker. While some people might have a metabolism crazily active enough where they could get away with wearing just a wind breaker, most of us need a little bit more than that to insulate us. It’s the same thing in the building world. The best way to measure the quality of the insulation used is to look at the R-value.
R-value is typically defined as the measure of thermal resistance a substance has. In other words, the greater the R-value, the better the ability of the substance to keep an interior conditioned to the occupants’ liking without overtaxing the HVAC systems. (Think about it. You could probably only wear a wind breaker in cold temperatures if you were running around, but how long could you keep that up?)
Just like the best winter coats have a wind-breaking shell coupled with some sort of fill to keep you warm, an effective building envelope needs to feature these exact same properties in order to be effective.
R-Value of Insulating Concrete Forms
Heat will travel three different ways, and will always seek cold. All three of these principles of heat travel should be considered when choosing materials for a building envelope. Obviously the product that allows for reducing ALL means of heat travel has a high true insulating value.
- Radiation - emitting heat through particles or waves
- Convection - the movement of heat through the movement of air
- Conduction - the transfer of heat between two materials due to differences in temperature.
R-Value is a Measurement of Conduction Only
ICFs have R-value in spades. Fox Blocks’s insulating concrete forms have a static R-value of 23, which easily bests code requirements, and is ideal for most any project seeking a green building certification. And just like an effective air barrier, effective insulation needs to be continuous (this is called continuous insulation, or CI). Like a compromised air barrier, conditioned air will seek gaps in the insulation, making it less effective.
Companies: Fox Blocks
Troy Gibson Troy Gibson has over 8 years of creative and strategic marketing management experience, ranging from sports marketing to retail marketing. He has been a part of the ICF industry for 6 years and is an USGBC LEED Green Associate. He focuses his efforts on communicating the benefits of a premium building envelope. Troy has a B.S. of Marketing from Northwest Missouri State and has a wife and child to occupy his free time.