The Sustainable Home Blog

“…buildings in the U.S. are the largest energy consuming and greenhouse gas emitting sector.”

I’m writing this on the same day that the U.N. Released the 2004 Report
on Climate Change. There is now very little doubt that human carbon
emissions are dramatically changing the climate and that the effects
will be devastating to millions of people around the world. I’m
probably preaching to the choir, but if you’re one of the few remaining
doubters then you might want to consider taking action and erring on
the side of caution if for no other reason than for the sake of our
grandchildren and future generations and a strategic reduction in our
dependence on foreign oil supplies.

Although much has been written on the topic, I think it’s useful and
pertinent to this blog to lay out the impact of the housing stock in
this country on the global warming problem.

For me the most compelling argument for a human cause to global warming
is the record in our polar ice packs. By taking core samples of ice and
measuring gases trapped within the ice, scientists are able to chart CO
2 levels and average global temperatures going back 450,000 years. What
this data shows is that for hundreds of thousands of years, natural
causes have caused fluctuations in global temperatures and CO 2 levels
that are consistent with each of our known “ice ages”. What is both
compelling and disturbing is that CO2 levels for the last 450,000 year
have never risen above 300 PPM and yet in last few decades have risen
to 378 PPM. Some scientists believe that if the current rate of fossil
fuel consumption continues, we could reach 840 ppm CO 2 by the end of
this century!

Figure 1. 450,000 Year Polar Ice Pack Record
Source: UN Intergovernmental Panel on Climate
Change

As the following data demonstrates, “combining the annual energy
required to operate residential, commercial, and industrial buildings
along with the embodied energy of industry-produced building materials
like carpet, tile, glass, and concrete exposes buildings as the largest
energy consuming and greenhouse gas emitting sector”¹.

Figure 2. CO2 Emissions by Sector
Source: Energy Information Administration

According to the U.S. Energy Information Administration, in the year 2005, the
residential sector contributed about 21% of the total CO2
emissions. Clearly the housing sector is a big part of the
problem and represents a huge opportunity to reduce CO2
emissions. The good news is that reducing emissions in new
homes by over 75% and in our existing housing stock by up to 50% is
well within our reach.

¹Architecture2030.org