leangreen.org recycled renovation on a low-budget ration

The sliding window for the rear of the house is one step closer to the long awaited re-install. After Tom and I initially put it on the tracks it became clear that even measuring 50 times may not be enough, perhaps 51 next time. We had hung the window about 3" too high which meant I had to take the track down 3", it's a good thing that Craftsman has a lifetime guarantee since my ratchet is retiring. While we have the window off we need to stain the interior and chisel out a mortise for the handle. Jen displayed her fine craftsmanship with this bit of woodworking last week, all the work on the shed really paid off.

On 4.20.2008, the New York Times Magazine published a Green Issue in honor of Earth Day. Their illustration of a home shows the annual carbon output of household devices. The water heater, furnace and air conditioner top the list while the refrigerator and clothes dryer run high. The intro explains that "a typical American single-family home is responsible for more than 11 metric tons of carbon emissions every year through its energy use."

What does a metric ton of carbon represent? A carbon emission is the release of carbon dioxide ( CO2) gas into the atmosphere, most often by the burning of fossil fuels such as coal and natural gas. CO2 is the most significant greenhouse gas responsible for global warming, but methane, nitrous oxide and other industrial by-products (like refrigerants) also contribute. These greenhouse gases absorb the sun's heat in the atmosphere, leading to rising surface temperatures and climate change.

A metric ton equals 2,205 pounds. A metric ton of CO2 is emitted when you:

• Travel 2,000 miles in an airplane
• Drive 1,350 miles in an SUV
• Drive 6,000 miles in a hybrid
• Run an average household for 60 days
• Run a computer for 10,600 hours

On a global scale, our metric tons add up quickly. In 2004, total worldwide CO2 emissions equaled 27 billion metric tons, compared to 18 billion metric tons in 1980 (see graphic). While North America's contribution has increased 27% over the past 25 years, Asia's emissions have more than doubled as developing countries become industrialized.

While the World Resources Institute targets a maximum worldwide average emission of 2 metric tons of CO2 per person per year for "sustainable" living on Earth, the International Energy Institute predicts that worldwide emissions will increase another 28% in the next 25 years even with "vigorous new policy measures."

These predictions lead to the question, "Why Bother?" Journalist Michael Pollen responds in his NYTimes article. For us, this house project is one way to make a best effort. The more we learn about our impact, the more we try to reduce our footprint in strategic, cost-effective ways. Our heating system, domestic hot water, and laundry drying will be solar powered. We'll be composting and gardening again. And while the SUV is still parked on the street, we're driving it less than 5,000 miles per year.

How do our efforts add up? To estimate our carbon footprint, we used the EPA's personal emissions calculator. Without counting transportation (driving or flying), we estimated our house's footprint at 9,263 pounds or 4.2 metric tons of CO2 annually. The calculator doesn't account for energy sources, however. For instance, in Denver, we could specify 100% of our power to be sourced from wind turbines, which has nearly zero carbon emissions. We don't have that option through PG&E in California (only 12% of power mix is from renewable sources).

A more holistic ...

Since we don't have enough redwood to cover the entire house, we will cover select areas with fiber cement panels. For the front, we're leaning toward a dark gray-brown to match the window frame and allow the redwood to stand out. For the back, we're leaning toward a desaturated green shade. Between the redwood and the douglas fir, there are lots of red-orange tones and the green seems to set them off without up-staging either. Then again, our palette has changed at least 20 times already. We're trying to minimize the number of wasted quarts of test paint. At some point, we just need to go for it.