SPF - Spray Polyurethane Foam
As much as 40% of a building’s energy is lost due to air infiltration. Gaps, holes and air leaks can make energy bills unnecessarily high. Spray foam performs as both insulation and an air barrier, closing gaps that let air escape and add dollars to monthly energy bills.
Air leaks that can waste energy and drive up utility bills can be filled with spray foam. Some common spots for air leaks that can be sealed with spray foam include the area behind knee walls, attic hatches, wiring holes, plumbing vents, open soffits, recessed lights, furnace flue or duct chaseways, basement rim joists, windows and doors.
Applying an SPF roofing system can improve a building’s strength. In fact, SPF roofs have effective lifespans that can exceed 30 years.5 SPF can help create a strong bond to protect the roof and can eliminate water seepage through weak spots. It can also be applied in a sloped manner to allow water to easily drain off the roof. The bond that SPF forms can increase a building’s resistance to wind uplift. During periods of high wind, a building with a spray foam roof generally experiences less damage than a building without SPF.
Spray foam prevents moisture and condensation throughout the building, helping prevent mold and mildew. Applying closed-cell spray foam in the cavities of the walls increases durability of the wall system because of its ability to conform and adhere to the surface upon which it is sprayed. A wall with spray foam insulation is better able to maintain its shape under duress than a wall assembly without spray foam.
Spray Foam and the Indoor Environment
SPF can make your home or building more comfortable in many ways. Spray foam helps minimize airborne sound transmission. Sealing a building’s air leaks prevents drafts, creating a more comfortable indoor environment and providing better indoor temperature control. Closed-cell spray foam acts as a barrier to water and vapor, helping to prevent condensation and water intrusion. Sealing gaps with spray foam can provide a barrier against pollen, dust and insects, which can be especially helpful in households with allergy sufferers. Spray foam helps minimize airborne sound transmission.
Open-cell Foam and closed-cell spray foam
There are two primary types of polyurethane spray foams, known as open cell and closed cell. They differ in densities and other aspects that can be beneficial or detrimental in a given application.
Closed cell foam is the denser and more common of the two types of polyurethane spray foam. The common measurement system for foam resistance to heat flow (i.e., insulation) is a foam’s “R-Value.” Closed cell polyurethane foams have higher R-values than other types of foam. Closed cell foams feature better insulation because of this resistance, and are also more resistant to water degradation or penetration, which includes moisture build-up. Moisture can eventually attract bacterial growth, promoting mold, which can eat away at wood and compromise structural integrity. Preventing moisture migration can help greatly curb mold growth.
Closed cell foams are also dense enough to insulate air, preventing drafts and keeping in regulated temperatures. This density also prevents mold growth because temperature control can cut down on humidity, which spawns mold. In order to maintain their resistance, closed cell foams are usually dense and strong, and resemble solids when they fully form. This strength not only helps to insulate buildings and appliances, but can also strengthen walls to which it is applied.
Open cell polyurethane spray foams are much less common because they were originally manufactured by only one company, and their R-values are much fewer than those of closed cell sprays. However, as their strengths were discovered, other companies began using them. Installation is similar to that of closed cells, but the effects are different. Open cell foam sprays expand once applied, allowing them to be installed in hard to reach, out of the way nooks and crannies. This includes wall and ceiling cavities that can be difficult to seal with closed cell foams. The expansion feature will hermetically seal the area and provide proper insulation. However, the R-value of open cell polyurethane spray foam is lower, this means its heat resistance level is lower, which can cause insulation failures in extreme temperatures. Because open cell foam is still very dense, it provides good insulation. Open cell spray foam does not have water resistance, though, and its lower strength provides less support to walls. It is also more permeable to vapor and air, and lower noise frequency ranges.
Another positive attribute of open cell polyurethane foam is its cost. Because of its disadvantages compared to closed cell foam spray, it is more affordable. This can be a great boon when an application does not require airtight seals and hermetic moisture prevention. Caution needs to be taken, though, that the less expensive alternative does not lead to more expensive repairs in the future. Establishing the needs of a given application are important before choosing which foam spray to use.
Soy-based foam
All spray foams contain petroleum-based chemicals. Some spray-foam manufacturers, including BioBased Insulation, Demilec, and Icynene, have "greened" their spray-foam formulas by reducing the percentage of petroleum-based chemicals in their B component, but not their A component. All spray foam insulations are petroleum based. Including soy based foam insulation. The difference is that soy based foam replaces a portion of that petroleum with soy.
A portion of the polyol resin — itself only a fraction of the B component — in these products has been replaced with a resin derived from soy oil or castor oil.
The U.S. Department of Agriculture has ruled that only 7% of a spray-foam product needs to be made of a renewable resource to be labeled as a bio-based foam.
Soy based insulation is just as good at insulating your home as traditional insulation. With soy based insulation you don’t have to worry about sacrificing quality in order to be more eco-friendly.
Most soy based insulation companies claim their insulation will help reduce monthly energy bills by 50% or more. Soy based insulation is more expensive than regular fiberglass, but the investment will pay for itself over time.
All spray foam insulation, including soy based, is green in the sense that they can help you dramatically reduce your energy bills.
