Y-wall is a high-quality flexible calcium silicate cement based building board, perfect for use as a fire rated sheathing board. Offering excellent fire properties as well as high levels of dimensional stability, Y-wall is an exceptional board for use in multiple applications. Y-wall is used primarily as a fire rated sheathing board or building board. Used extensively on both steel frame and timber frame structures, Y-wall is used behind all types of façade solutions, as well in ceilings offering a non-combustible classification.