The cost of heating or cooling your home is probably your biggest energy expense. A one-time investment in insulation will save you money every year and will also keep out unwanted noise.
If you’ve ever opened up the wall of a home built before about 1950, you’ve probably been shocked to find little or no insulation—or at best some crumpled newspapers. And even the earliest serious attempts at insulation with fiber glass look quaint now. Cavities were often only partially filled. Water from outside often leaked in around windows and doors and damaged the insulation. Of course, homes were so leaky prior to the 1960s that walls dried out quickly, so mold wasn’t a big problem. The rules of the game are very different today. Homes are built tight—with no tolerance for sloppy insulating.
Building scientists (a new breed of experts) now have a deep understanding of how insulation works. They’ve learned that factors such as air infiltration, dampness, and age can dramatically affect performance.
But they also recognize that insulation is part of an energy saving system, not a standalone solution. Each type of insulator has its strengths. Good results can be achieved with any insulating material if it’s combined with the right housewraps, tapes, and construction details. Here’s a brief overview of the latest advances in insulation technology.
FIBER GLASS INSULATION
> Renewable and recyclable
> Familiar to contractors
> Field proven for decades
> Requires careful installation
> May need an additional air infiltration barrier
FIBER GLASS: INSTALLER FRIENDLY
Fiber glass insulation in batt form is probably the most familiar insulating product. Changes in recent years have affected the composition of chemical binders that hold the product together, along with the size of the glass fibers. Many brands have removed or reduced toxins such as formaldehyde from their products. At least one company has begun to offer a hybrid spray foam system. Other brands have improved the performance and handling of blown-in fiber glass. Some brands contain up to 40% recycled glass.
SPRAY FOAM INSULATION
> Fills gaps and cavities completely
> Provides its own air barrier
> High R-value per inch
> More expensive than competing products
> Requires special equipment/skills to install
DRYVIT OUTSULATION RMD
This exterior finishing system incorporates rigid foam—expanded polystyrene into its multi-layer wall finish. The result is a durable, paintable wall with the appearance of granite, stucco, brick, or other materials—depending on preference. The system is especially effective at removing the problem of unwanted heat transfer through the framing studs. www.dryvitisgreen.com
OWENS CORNING ENERGYCOMPLETE
Installation of this hybrid system involves spraying a thin layer of low-expanding foam that acts as an air infiltration barrier and seals tightly around plumbing, ducts, sills, and other key areas of a home’s shell. Installers then fill the rest of the cavity with fiberglass. The result: good insulating results at lower cost than full cavity spray foam. www.ocenergycomplete.com