Every roof is constructed differently. Roofs where the various roof components can be easily separated (mechanically attached/induction welded membrane and mechanically attached insulation) are the easiest to remove and recycle. It is recommended that if the existing insulation is dry and in good condition, it can be left in place. Today, insulation is typically the most expensive part of a new roof. By reusing the existing insulation, you save money, salvage the valuable existing R-value of the insulation, and minimize what goes to landfill. Recycling a mechanically attached or induction welded PVC roof membrane is relatively simple. It is recommended that with each re-roofing project, regardless of the membrane type, the existing roof system be evaluated to determine what can be saved and what can be recycled and whether the insulation and fasteners can be reused. This will lead to the least amount of roofing material being landfilled.