In recent years, there has been an increased awareness about the environmental impact of buildings and
construction materials with increasing regulatory pressure to reduce this impact. Properly assessing this
impact is the first step towards achieving a green construction sector. Asphalt roofs are an important
component of the construction sector in the United States. GaBi, a life cycle assessment (LCA) software
package, was used to evaluate the greenhouse gas (GHG) emissions of an atactic polypropylene (APP)
asphalt roofing product. Due to the complexity of the manufacturing process, an average approach where
the raw materials and energy use to manufacture the product over an entire year were summed up and
the results were normalized per functional unit of the product. Global warming potential (GWP) was
used to evaluate the overall GHG emissions. The GHG emissions were estimated to be 75.2 kg CO2-eq per
roll. The manufacturing stage was found to be responsible for a majority of the GHG emissions. Certain
shortcomings in the LCA study were identified and suggestions to reduce GHG emissions were made.
This study differs from previous studies on roofs in that it focuses on the environmental impact of roofing
product itself, unlike previous studies that have investigated energy efficiencies or reduction of environmental
impact as part of a larger study