Building Green, as I see it, is only partly about energy efficiency. The real goal for most of us is “affordable comfort.” The less you waste, the less you spend. The less you spend in controlling unnecessary heating, cooling, and water use costs, the more you have left over to spend on other things.
It all works best if the solutions are simple and inexpensive enough to be widely adopted and put into use. Consider this: if every house in America were properly insulated to Energy Star standards, we could stop importing foreign oil. That’s how much is wasted — yes, wasted — through leaky ducts and attics nationwide. Yours, mine, every house on the block, every town in the county. Insulating, air sealing, and moisture control through ventilation are the key concepts.
But we’re not talking about saving the planet here. The real goal, the one we can get to, is “affordable comfort.” You could, for instance, upgrade your 30-year-old furnace to a new 95 percent efficient model, and save up to a third on your gas heating bill. While you’re at it, look at all your ductwork that’s visible in the subfloor, attic, and garage. If you see duct tape, you can figure that 30 percent at least of your warmed air is going to heat those three areas. Duct tape was never intended for use on ducts; its use is not sanctioned by the California Building Code. Water-based mastic, properly applied, keeps the warm air inside the ducts, and the cold air out.
If your ducts are wrapped with fiberglass insulation, and the insulation has become discolored and dirty in some places, that is because there is a duct leak underneath, and the fiberglass is acting as a filter for the unconditioned air being drawn in. It’s also adding minute particles of the insulation itself to the air being circulated throughout your house. Not a pleasant concept when you think about it.
Take off a warm-air register and look at how the metal supply boot is connected to your floor or ceiling. If it’s not sealed to the floor, the gap you see connects directly to your crawl space or attic, and every time your furnace kicks on, some of that nasty unconditioned air is drawn right into your house.
The most effective way to deal with these is through the services of a CGBCA retrofitting contractor using a blower door and a duct blaster to find and fix the worst of your leaks, Insulating, controlling duct leakage, air sealing, and moisture control through ventilation are the key concepts to the whole-house, systems approach. This is the new building science, applied to the construction and home renovation industry. Carefully done, by trained professionals, it results in the “affordable comfort” that is the real goal.
Pacifican David Hirzel has been a certified green building professional since 2006.
