A method for recycling glass mat waste, wound rovings, and other products includes providing a source of glass mat, or a plurality of rovings, for example on a roll, and routing the glass mat or rovings into a submerged combustion melter. An unwind system and a pair of powered nip rolls, powered conveyors, or other arrangement may work in combination to provide a substantially consistent rate of material into the melter. The melter may operate under less than atmospheric pressure to avoid fumes escaping the melter. A slot in the melter allows ingress of the glass mat or rovings into the melter, and a glass mat former such as a folder may be used to ensure that the mat fits through the slot. Alternatively, the glass mat may be cut by a slitter prior to entering the slot.