Back to the office paperâ¦ A ream of Craigâs paper weighs 3 pounds (1.4 kg). At the lifecycle factor of 2.56 mentioned above, each ream would require 3.6 kg of wood. And at 3000 reams per year his office is using 10,752 kg of wood. Based on the average tree weight above, this amounts to 16 trees per year, or about one every three weeks.