Frequently Asked Questions About Spray Foam Insulation
What is Spray Foam? (Spray Polyurethane Foam - SPF)
Spray Foam is made of a two part liquid mixture consisting of an isocyanate and a resin mixture, These two chemicals are mixed at a perfect ratio to insure the foam will adhere perfect to the substrate(wall) and receive the proper (R-value). These chemicals are pumped through a specialized heating and pressurizing unit known as a reactor. The fluids are completely separate until just before leaving the gun, and mixed at specific temperatures and pressures. There are two types of foam. One is a closed cell and the other is an open cell.
What is the difference between ‘open’ and ‘closed’ cell insulation?
The differences are in the R-value and whether or not there is a need for a poly vapor barrier to be put over it. Open cell (0.5lb) insulation uses air pockets to help in the r-value but requires a vapor barrier to be put over top of it. Closed cell (2lb) insulation does not require a vapor barrier on any substrate after being applied at 2" thickness. The closed cell foam that Cold Country Spray Foam uses is Insulthane Extreme, which at 3.5" thickness, has a long term thermal rating R-value of (R-20.4).
What does R-value mean?
R value insulation ratings are used to measure insulation ability to resist heat flow. The higher the R value, the more effective it is. Home insulation should be purchased based on its efficiency value. Most contractors initially try to sell customers on more then 3 inches of spray foam in a wall cavity. At 2 inches of spray foam, after application your resulted (E-Value) of the product comes up to 89% more efficient. At 3 inches, the area sprayed is now 95% more efficient! After 3 inches, there isn't really a point to apply more product, because its just costing you more money! Don't be fooled by how the word R-value works, the efficiency in your home is what really matters!
What is a LTTR (Long Term Thermal Rating)?
A rating system we use to see how insulation performs in the long term. Most standard testing is for the R-value immediately after it is installed. Ask what the LTTR is-this will give you a true value of the spray foam insulation that you are installing in your project may it be a house, or building.
What makes Spray Foam better than conventional fiberglass insulation?
A batt of fiberglass insulation is that its (LTTR) is substantially reduced over time. The (R-value) rating on a bag of fiberglass insulation are very deceiving. When a bag of insulation (pink) says (R20) it means that it will provide that rating if it is installed correctly, without any air movement nor gaps. The (LTTR) of an (R20) fiberglass batt is at best actually rated at (R12). This is because it will sag and gap for a variety of reasons (gravity, house shifting, pulling wires through wall space, vibrations in house, etc.) For every 1/8" gap you will lose 50% of the (R-value). Spray foam insulation is guaranteed to never gap, sag or crack, while fiberglass insulation does not guarantee that.
Can polyurethane foam burn?
Polyurethane foam insulation is listed as a combustible insulation under the building code. The foam does have a fire retardant in it, which means it will not support a flame. If you pull the source of flame from it, it will stop burning. Building code requires a thermal barrier to be put over all foam insulation (½” drywall meets all thermal barrier standards). If wanted, an after coat of fire retardant can be applied if no such thermal barrier is applied (drywall) depending on the project and rules applied to the job.