Insulating Wisdom

You can’t see it, you usually can’t touch it, and you’ll forget it’s even there, but insulation has a gigundo impact on just how green your house is … or isn’t. Any major remodeling project is a chance to determine what type of insulation (if any) exists in your walls and attic, what shape it’s in, and what upgrade or new insulation would best serve your purposes.

This particular decision is not just a matter of being green. The right insulation makes your home more comfortable, more energy efficient, and creates a healthier interior environment. Along the way, it can save you bundles of cash.

The majority of homes are insulated with Fiberglass batting, which remains the most widely used insulation. However, Fiberglass can be difficult to work with, can irritate the skin, eyes and breathing passages, and is far from a green material. Even worse, older homes may still have urea formaldehyde foam insulation (UFFI). The formaldehyde is a carcinogen that can compromise indoor air quality for years and possibly decades after installation. 

Thank goodness you have a bevy of green insulation options to pick from! These come in the same basic forms as traditional materials: loose-fill blown-in (or spray-on) versions, or batting.

Blown-in or spray-on expanding foam insulation is incredibly effective, quick to install, and long-lasting. In the past, this product meant dealing with chlorofluorocarbons (CFCs) and hydrofluorocarbons (HCFCs) that depleted the ozone. Today, however, there are green spray foams that, while still urethane-based, off-gas virtually no VOCs and perform beautifully. Demilec USA (www.demilecusa.com) manufacturers a couple of examples, including Sealection and Heatlok Soy. Sealaction uses water for the delivery system and is an open-cell foam, while Heatlok Soy incorporates recycled plastic, and includes soy and vegetable oils, and is a closed-cell foam. Both are certified through the GreenGuard program, and the National Association of Home Builder’s “Green Approved” qualification.

Closed-cell products are usually denser, stiff and offer a higher R-value than their open-cell cousins. They also resist air, water vapor and moisture penetration better than any other insulation. However, this superior performance comes at price: closed-cell foams are more expensive overall, and cost more per R-value, than most other options. Generally, closed-cell products are reserved for areas where having a highly effective air and moisture barrier are real concerns.

Cellulose blown-in insulation is an even more eco-friendly option. Although the R-values pound per pound are lower than urethane spray foam, cellulose insulation can still offer from R-13 to R-60, depending on the thickness of the insulation. The knock on early versions was moisture retention; they were blown in wet and often retained moisture that led to mold and mildew growth. These days, companies like GreenFiber (www.greenfiber.com) make cellulose products that are not only as much 90 percent recycled paper, they are also blended with borate or similar treatments that prevent mold growth, insect infestation, and serve as fire retardants.

Cellulose insulation is competitively priced with other types, and it is often sold as a DIY option. You can buy blowers and the related equipment, or rent everything you need from a local rental center. Keep in mind, though, the job is messy and must be done correctly to realize the maximum R-value and other benefits. When installed correctly, blown-in and sprayed-on insulations create tighter air seals and provide better sound-deadening properties than other types of insulation. That's why the vast majority of homeowners opt to use certified professionals when going with blown-in or sprayed on insulation.

Recycled cotton or denim batting such as UltraTouch by Bonded Logic, Inc. (www.bondedlogic.com) is some of the most truly green insulation available. UltraTouch includes approximately 80 percent post-consumer waste, and releases no VOCs. The batting is perforated so that you simply measure, tear, and install. The material doesn’t irritate skin and breathing passages as Fiberglass does, and is Class-A fire rated. The company also produces UltraTouch cellulose insulation.

A less common but potentially effective and environmentally responsible option is mineral wool. There are two types of mineral wool: a version called rock wool that is formed from natural minerals such as basalt; and slag wool that is processed from blast-furnace slag (the scum floating on top of molten metal). Mineral wool is available as loose fill and the much more common blankets and stiff boards. Companies such as Thermafiber (www.thermafiber.com) provide the insulation and the tools needed to work with it. The material typically includes about 75 percent post-industrial waste and is installed in roughly the same way as Fiberglass batting is.

The place to start in choosing any insulation is the R-value. Balance selecting the highest R-value possible against your budgetary constraints, and where you live. A high R-value will provide a bigger return on investment in the frigid Northeast, than it will in more temperature southern States.

You’ll also want to pay close attention to the technical specs for the insulation you’re considering. Review the manufacturer’s claims regarding “settling” (the tendency for wall insulation to slide down in the cavity, leaving little or no insulation in spots—something that can even happen with traditional Fiberglass batts). Establish the green cred of the insulation you’re leaning toward, by checking out if it qualifies for LEEDs credits.