environmental impact of construction of the manufacturing facility
itself including all the equipment and the machinery and the
financial costs due to labor and maintenance were not a part of this
study.
Some of the raw materials used are the result of recycling at
other facilities. Since the recycling history from the suppliers was
unavailable, all raw materials were treated as primary raw materials,
i.e. produced from natural substances without any recycling as
reported in the US LCI database. Some of the finished asphalt
roofing product that may have been defective or lacking in some
way was reprocessed and used as feedstock instead of being discarded
or sold at a discount. The average amount of rework that
comprises each roll is listed in Table 1. It may be noted that the
manufacturing facility generated a significant amount of solar energy
on site. This factored into the LCA study as a reduction in the
overall electricity consumption. Table 2 shows all the energy resources
involved in the life cycle normalized to represent one roll.