GOOD HOUSE BAD HOUSE Retrofit Options for Sustainability

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1 GOOD HOUSE BAD HOUSE Retrofit Options for Sustainability By Paul Shippee Wrapping all wood-frame walls with thick foam insulation panels illustrates a basic economic principle of reducing heat loss. When adding insulation, in new or old homes, you pay for the purchase once and reap energy savings year after year. Sustainability means living without driving, Alice quipped during a recent Baca conversation. We were standing on white snow under a blue Colorado sky. I happened to look up and notice a heart-shaped gray cloud moving in to block the sun when Alice corrected herself. Come to think of it, she said, there s nothing wrong with driving. It s what you put in the gas tank that s the problem those ancient sunlight fuels we re depleting. Alice s thoughtful statement put me in a philosophical mood; how do you translate that problem into action? My thinking moved naturally toward houses, the ones that are already built. If you own a house, then it seems easiest to start there. You can cut your heating bills in half with a caulking gun and some free bubble wrap, right?

2 Blowing lots of loose insulation into attic spaces is the most cost effective place to add insulation. This is because it s cheap and most heat is lost through poorly insulated ceilings. Stand-alone houses lose a lot of heat in winter mostly through window glass, ceilings and cracks everywhere. The first dollars you spend (invest) to save home heat should be spent on these areas. On a cloudy morning last week I saw a house with sleeping bags hanging in large south-facing windows. Do-ityourself items like caulking cracks, insulating windows at night, adding attic insulation and perhaps storm windows is a way to double your investment with sweat equity and recoup a rapid payback as fuel prices rise. State weatherization programs usually attack these items first for these same reasons. It s all low hanging fruit. Window insulation can be a cost effective application of added insulation. Heat loss out windows can be excessive on those long, cold winter nights. Many options are available for interior décor and convenience. A friend told me he stapled bubble wrap to a roller shade and saw a quarter inch of ice on the glass in the morning after a very cold night. Another bubble wrap fan saw green plants grow in a funky solar greenhouse in midwinter where they never

3 did before. Results! Window treatments can range in cost from a few cents per square foot for bubble wrap and roller shades up to an expensive $15 per square foot for attractive triple cell pleated accordion designer shades that are also translucent. As a compromise, I am considering using silk draperies at $10 per yard (that s about $1 per square foot for materials) Thermostat reduction and wool sweaters bring further savings for free. Older folks may need warmer rooms. My Dad cut his heating bill more than in half in a smallish conventional New England home by replacing old double-hung leaky single glass wood windows with new tight vinyl double glass windows. Keeping the old storm windows in place resulted in economical triple glazing. Adding an extra foot of insulation in the attic (not possible with cathedral ceilings) and keeping the old oil burner clean and running efficiently rounded out the program for both big savings and a warm house. Fortunately, for the sustainability picture there is a lot of slack available for reducing energy consumption in the old built environment in America. Add-on solar greenhouses come in many configurations. They are multifunctional sunspaces that collect solar heat, reduce heat loss, and provide attractive green living environments. On a larger scale, as a solar designer and contractor working in Boulder I helped convert several older homes for energy conservation. Some century-old solid brick homes with limited south yard space called for installing a glass wall over a one- or two-story south brick wall, and wrapping the other three sides with insulation and new siding. A Trombe wall passive solar heating system with plenty of interior thermal mass was achieved along with a tighter building envelope.

4 Some of the newer wood frame houses seemed to call for a sunspace (solar greenhouse) added on to the south side when there was yard room. A fan was often employed to carry excess warm air to the north rooms and perhaps a passive domestic water tank painted black was placed in the sun behind the glass. These attractive improvements formerly qualified for hefty energy tax credits and may soon do so again. Stay tuned. Domestic water heating and space heating by active solar systems (think solar collectors) might also come into the economic picture, especially if attractive tax credits become available on both the federal and state levels. In Boulder we designed and installed both air and water active solar heating retrofits that cut heating bills by one half to two thirds. An attractive, powerful and efficient solar greenhouse addition heats an older home in the mountains of Cold Springs, Colorado These systems tend to have a long life (20 plus years) with some maintenance costs along the way. A domestic hot water solar system retrofit can cost $6-10k and an active space heating solar system will run around $100 per square foot of collector area. Since these systems are not cheap and the payback time is uncertain (because it is tied to future fuel prices) the implementation of generous state and federal energy credits is an extremely important economic incentive. The main reason for this is that the alternative fossil fuels (propane, coal, electric, etc.) are already heavily subsidized by governments who donate corporate tax breaks, limited liabilities, oil depletion allowances, etc. On top of that who can calculate the environmental and human and political cost of both overt and clandestine wars fought for the control of the world s declining fossil fuel resources? At the very least you can bring your dog in on cold winter nights to contribute around 75 watts of body heat energy. In areas where pollution from wood burning stoves is limited, fossil fuel energy can be saved by using this

5 renewable source. Unlike fossil fuels, burning wood is relatively carbon neutral because the CO2 released was sequestered in the wood only decades before. A food and heat producing solar greenhouse can provide a lush green living space for winter warmth, fun and pleasure. A website available for tracking the latest developments for state and federal tax credits can be found at and other natural building and solar applications information is at where upcoming renewable energy education workshops are announced periodically.