While it is of the utmost importance to keep our forests intact, it is of equal importance to take a hardline at curbing CO2 emissions. A new study published in the Journal of Sustainable Forestry has found that concrete and steel based construction requires more energy to build and emits 10X the amount of CO2 compared to wood. A wood floor beam takes 80 megajoules (mj) of energy per square foot to construct, and emits 4 kg of CO2. The same amount of floor space, if supported by steel will require 516 mj to build, and will emit 40 kg of CO2, and a concrete floor of that size takes 290 mj to build and emits 27 kg of CO2.