Smarter Weatherization


So, if you read our other installment regarding quick ways to weatherize your home for the winter months (Eco, page 48), you may be asking yourself: “What products will best help me do so?” We won’t be discussing brand names per se but, rather, product alternatives that perform the same as other products in their class but are safer for you and the environment. First, a little background:

Indoor Air Quality (referred to as IAQ) is a major tenant of green building. Consider that we spend the vast majority of our lives indoors, yet our indoor environments are typically two to five times more polluted than our outdoor environment. Is there any wonder respiratory illness and cancer rates have increased steadily over the last 60 years?

What is the major source of indoor pollution? Well, frighteningly enough, it’s the paint on your walls, the stains and finishes on your furniture and cabinets, the adhesives under your floor, the cleaners you use, and the aerosols you spray in the air. In fact, many, many products in your home give off-gas chemicals into your rooms for years, which is why Volatile Organic Compounds (or VOCs) are beginning to show up on the radar of our collective consciousness. VOCs are defined by the EPA as smog-forming compounds, and it’s a safe bet that, if a chemical is forming smog, it’s go- ing to have an adverse affect on your health when inhaled. While the EPA’s list of VOCs does not comprise all the toxic compounds floating around in your paints, sealants, and adhesives, it’s a good metric for guiding your buying decisions. (You can begin to become familiar with these toxins at:

Now, back to which products to use.

Common weatherization techniques require that you seal gaps around your windows and doors with caulks or expanding foam sealants. Most ex- panding foam sealants, like many aerosols, use chlorofluorocarbons (CFCs) as the expanding agent. CFCs, when they enter the atmosphere, break apart and emit chlorine atoms that deplete the ozone layer. Fortunately, options are now available in zero-or low-VOC form. Instead of buying expanding foam sealants that contain CFCs, look for products that use hy- drofluorocarbons, or HFCs, which do not contain chlorine or bromine and, hence, do not deplete ozone.

Also, check for labels that have the designation: “No Urea Formaldehyde Added.” Formaldehyde is a human carcinogen and is listed on the EPA’s list of VOCs. In small amounts, form- aldehyde is not dangerous; it occurs naturally and exists in tiny amounts in all living species. The problem is, product manufacturers use a syn- thesis of formaldehyde and urea (another VOC) to form adhesives, bonding agents, and solvents. Urea formaldehyde is prevalent in a shocking number of consumer products that over time break down and off-gas formaldehyde into your home.

In the weatherization article (Eco, page 48), I mentioned that to further decrease energy bills, you may need to add insulation in the unconditioned spaces of your home (wall cavities, crawl spaces, and attic). But guess what?—Most of that batt insulation you normally would run out and buy (you know, the cheap pink stuff) is chock full of formaldehyde. On the one hand, you would be increasing your energy efficiency, saving money, and reduc- ing your impact on the environment; on the other, you would be exposing yourself and loved ones to a prod- uct that, even when confined to your attic or inner wall cavities, leaches toxins into your conditioned living space. Once again, however, there are better, though slightly more expensive, alternatives. Recycled cotton insula- tion that uses natural boric acids in place of formaldehyde performs just as well as formaldehyde-laden products but without the negative side effects.

For best energy performance, many contractors and homeowners are turning to blown-in, expanding foam insulation (also called extruded poly- styrene foam or expanded polystyrene foam). In this process, small holes are cut in your outer wall and foam insu- lation is blown in that expands to fill every nook and cranny of the wall cavity. But not every one of these prod- ucts is made equally. It’s up to a discerning consumer to find the smarter product.

Regardless which products you ultimately decide to use to increase your home’s energy efficiency, remember that each has upsides and down- sides, and you should carefully weigh the benefits against the disadvantages. Do your research and find products that are designed smarter. Every manufacturer’s website has MSDS sheets (Material Safety Data Sheets) that list the technical product specs including VOC content. Check the VOC contents against those allowed by the Austin Energy Green Building Rating System, the US Green Building Council’s LEED (Leadership in Energy and Environmental Design) rating system, or the California Air Resources Board (CARB) standards.

Knowing exactly what you’re using will give you peace of mind as you weatherize for the winter and will, more than likely, change your purchasing habits for a lifetime.