Spray foam, also known as SPF, is a type of building insulation used as an alternative to fiberglass. This combination of isocyanate and polyol resin forms a foam mixture that expands when applied to roofing tiles, wall openings, sprayed onto concrete slabs, or placed in previously drilled holes.
TYPES OF SPRAY FOAM
There are two categories of spray foam insulation: open cell and closed cell. Open cell insulation includes small, spongy cells that are not closed completely. It is not as expensive due to the fact that it uses less chemicals for production. Even though it provides adequate protection for interior walls and sound reduction, and it does not provide a barrier against water vapor. Closed cell insulation has a dense and more compact cell structure, and provides an adequate barrier against air leakage and water vapor. It is recommended for outdoor use, roofing, or anywhere insulation is needed in the home.
ADVANTAGES
Spray foam insulation has been known to help lower utility bills and energy costs and protects air from filtrating through windows, doors, and walls. Mold and mildew is also reduced due to inhibiting the formation of moisture which causes wood to decay and produces allergic reactions. It is an excellent noise reduction barrier preventing sound conduction through the floor, walls, and ceiling. Homes with spray foam insulation are often entitled to state and federal tax deductions. Spray foam insulation has a high quality of thermal resistance, blocking three types of heat transfer:
• Conductive heat transfer (how easily heat moves from the outside to the inside)
• Radiant heat transfer (occurs through a vacuum by a solid or fluid transparent medium)
• Convective heat transfer (heat is carried through the fluid or gas)
DISADVANTAGES
Isocyanates can adversely affect health by causing eye irritation, gastrointestinal problems, and irritation of the respiratory tract. It can cause inflammation of the skin and rashes with direct contact. Exposure to isocyanates can aggravate asthma, cause chemical bronchitis and overall respiratory irritation. Other health issues may include:
• Hypersensitivity pneumonitis (HP) with headache, fever, and muscle aches
• Dry cough
• Breathing difficulties
• Fatigue
• Chest tightness
• Weight loss
• Blurred vision
Caution must be used when applying foam insulation, and it is highly recommended that respiratory protection is used due to emission of toxic gases. However, after the spray foam has dried, it becomes non-toxic.
It is suggested that professionals are contacted to apply spray foam insulation. Due to its expansion, walls and ceilings can be damaged considerably if foam expands improperly. Structural problems and rotting can develop if applied to the underside of wood-framed roofs since the moisture and water will no longer drain or evaporate properly.
OTHER USES
Other uses of spray foam insulation include:
• Floatation for boats, floating docks, ships, and barges
• Industrial insulation for pipes, tanks, freezers, and coolers
• To increase the structural strength of airplane wings
• Plugging mine shafts
• Taxidermy stuffing
• Movie & theater sets
For those who wish to do projects at home, cans of spray foam insulation are available at home improvement stores.
About The Author
Jason Denton is a writer for Foam It Green!, the maker of the DIY spray foam insulation kit, available at Home Depot and other great places.