The treatment and lining of two paintings to fiberglass fabric with Beva 371 adhesive are described. An oil painting by Rembrandt Peale, 91 x 72 cm on deteriorated acid fabric, with an x-shaped tear and cupping paint was treated. After consolidation of the edges of the tear with soluble nylon, the repair was accomplished with an epoxy adhesive. The prepartion, attachment and removal of a heat-seal facing of Promatco tissue and Beva adhesive; deacidification of fabric support with calcium hydroxide; resizing with Beva and CaCO₃; and application of Beva 371 to the fiberglass sandwich lining fabric are described. The treatment of an outsized painting by Gerrit Cup (164 x 273 cm), oil on glue lined seamed canvas was used to illustrat the preparation of large fiberglass heat-seal laminates.