This study is an extension of the Life Cycle Assessment (LCA) for Low Carbon Construction Project. The Oregon Department of Environmental Quality selected mechanical, electrical, and plumbing (MEP) and tenant improvement (TI) as research topics of interest to investigate because there is very little data on these environmental impacts. This study presents estimates of material quantities and environmental impacts for commercial office buildings in the Pacific Northwest. This study is funded by the Charles Pankow Foundation, the Oregon Department of Environmental Quality, and Skanska USA.