Durock and similar cement-based products are designed for uses where it may be exposed to water. It’s not waterproof but it will not disintegrate or lose its strength when wet. You should allow it dry thoroughly, however, before using it.

How can I make my durock waterproof?


Quote from Youtube video: Apply the first coat at a wet film thickness of 15 to 20 mils. Be sure to overlap all adjoining sections of the membrane by a minimum of two inches.

What can I use to waterproof cement board?

Quote from the video:
Quote from Youtube video: Use painters tape to protect the tub from the silicon and the waterproofing. Next fill the gaps between the cement board and the tub with silicone. Then allow it to dry before you begin the next.