Waterproof protection for joists that prevents rotting of structural timber under exterior floors, such as patios and balconies. The joist guard is a 0.6 mm self-adhesive waterproofing membrane made of elastomeric SBS bitumen and a polyethylene film on the surface. The underface is composed of a silicone film easily detachable. For reference, 10 cm rolls are ideal for 5 cm-wide joists, while 23 cm rolls are used on double joists at the perimeter of the structure and to seal the joint between the wall of the house and the patio.

Provides waterproof protection for exterior joists Substantially extends the service life of patios at a low cost Provides additional protection against rotting of structural lumber under exterior floors Barely visible between the boards (not included) Flexible, self-adhesive and self-sealing around screws and nails (not included) Made of elastomeric bitumen with a polyethylene surface Roll: 4" x 75