Research into pyrolysis-based recycling of sheet molding compounds (SMCs) to recover glass fiber for reuse has indicated significant pre-existing tensile strength damage in the shredded recycling input materials. This loss in mechanical durability inherently hurts the value proposition of recycled glass fiber by limiting reuse of the fiber for reinforcement. In this study, the mechanical properties of glass fibers at each step in the first lifecycle of an SMC material are measured to assess the extent of cumulating fiber damage prior to recycling and identify potential causes of this degradation to maximum fiber tensile performance.