Loctite PL Roof and Flashing Polyurethane Sealant is a premium quality professional grade sealant developed especially for forming permanent, weatherproof seals for gaps and joints on roofs and chimneys. The durable formula has ± 35% movement capability allowing for shifts inbuilding materials without jeopardizing the seal. PL Roof and Flashing can withstand harsh UV rays and other harsh exterior elements for a long-lasting durable seal. Loctite PL Roof and Flashing is a low VOC formula that meets strict federal and state guidelines.