PREGYFLAM A1 BA13 is a plasterboard,15 mm thick, tapered edges, with a gypsum core densified and admixed with glass fibers and vermiculite and coated on both faces with fireproof cardboard with low calorific value, for the construction of walls,linings, ceilings or coverings where high resistance to fire performance is required or for the protection of structural steel elements, in combination with the A1 class of reaction to fire. The particular nature of the cardboard requires, for the execution of the joints, the use of Siniat compound and perforated paper tape.