Insulation

One of the key elements of the building envelope is insulation because it can help dictate comfort for the family. Use of insulation helps create the peace of mind that comes with knowing we have made an investment that not only serves our family, but is energy and cost-efficient. A variety of plastic products may be the solution for the home, including housewraps and foams: spray polyurethane foam (SPF) and rigid foams made with polyurethane (Polyiso), extruded polystyrene (XPS) and expanded polystyrene (EPS).

The same material we use to wrap our bodies -- in the form of Gortex clothing -- or to ship our goods -- in overnight packages - can also wrap our building envelope. Plastic housewrap, coupled with insulating plastic foams and sealants, adds another layer of protection to a home, and has been shown, in the Franklin Associates Study, to reduce infiltration of outside air by as much as 10 to 50 percent. By reducing air infiltration of outside air, the energy required to heat or cool a home is reduced - saving the average homeowner thousands of dollars over the life of a 30-year mortgage. Housewrap can also help reduce airborne pollutants that otherwise penetrate your home’s envelope.

Spray polyurethane foam (SPF) and rigid foams made with polyurethane (Polyiso), extruded polystyrene (XPS) and expanded polystyrene (EPS) are growing solutions for insulation systems.

SPF conforms to the surface to which it is applied and forms a seamless layer of insulation, thus filling energy-wasting holes and gaps around pipes, outlets, windows and more. Since SPF fills in gaps and seams during application, it is increasingly being used as an air-barrier in buildings. The material -- cut into sheets, slabs or any desired design, as well as sprayed to meet specific building code requirements or custom designs -- serves as a durable design solution since it often arrives at the job site as a liquid, saving on transportation costs and reducing waste.

This beneficial ‘air barrier’ effect can be achieved by rigid polyurethane (Polyiso) foams installed properly with taped seams. Structural insulated Panels (SIPs) also demonstrate this same beneficial air barrier trait. SIPs can be made from Expanded polystyrene (EPS) or Extruded polystyrene (XPS). A SIP is two layers of 5/16th inch OSB with the expanded or extruded polystyrene encased between those two layers forming a rigid wall structure without normal ‘studs’ being needed. See the June issue of Modern Materials magazine for National Association of Home Builders wall performance tests showing how plastics building materials can outperform typical ‘stick and batt’ construction under real-world windy conditions.

Can SPF and rigid plastic foam insulations (SIPs, Polyiso, EPS and EPS) exhibit green characteristics? Yes. By inhibiting heat flow and helping create air barriers, plastic building products can help save energy heating and cooling the structure over time. This lessens the environmental ‘footprint’ of the building over time. Savings in manufacture of plastic building products have been validated as well, to show that plastic materials save approximately 467.2 trillion BTU of energy a year as compared to alternative materials. The energy saved is enough to meet the average annual energy needs of 4.6 million U.S. households.

According to a 2000 study by Franklin Associates, for the entire country, the annual savings in energy cost would be $2.58 billion or $128.6 billion over 50 years if all houses were insulated with plastic foam insulation.

In commercial applications, SPF is typically applied over existing roof systems, which avoids scrap and waste while the product also provides exceptional energy savings through high R-values with no seams, longevity, resistance to leaks, and little degradation due to UV rays.