The thickness of waterproof backing boards varies depending on the application, material type, and specific requirements.
Generally, waterproof backing boards used for ordinary indoor waterproofing (such as bathroom walls) are approximately 6-12mm thick. In applications requiring higher strength, such as roof waterproofing, the thickness may reach 12-25mm.
For special projects or situations with high requirements for the load-bearing capacity and other performance characteristics of the waterproof backing board, the thickness may exceed 25mm. The specific thickness must be determined based on the actual project design and waterproofing requirements.