How do I waterproof a shower curb?

Proper shower curb waterproofing is critical to prevent water damage and requires multiple layers of protection. The curb is one of the most vulnerable areas in a shower because it's constantly exposed to water and needs to redirect it back into the shower pan.

The waterproofing process starts with the curb construction itself. The curb should be built with a slight slope toward the shower interior (about 1/4 inch per foot) and must be properly integrated with the shower pan liner or waterproof membrane. In Ottawa, this work typically requires building permits when part of a larger bathroom renovation, as it involves plumbing and structural modifications.

For effective waterproofing, you'll need a liquid membrane system or sheet membrane that extends from the shower floor, up and over the curb, and onto the bathroom floor. The membrane should wrap completely around the curb, creating a continuous waterproof barrier. Popular systems include Schluter-Kerdi, RedGard liquid membrane, or similar products. The membrane must extend at least 6 inches beyond the curb on the bathroom side and tie into the shower pan waterproofing.

Critical details include proper corner treatment and penetration sealing. All corners where the curb meets walls need reinforcing fabric or pre-formed corners, and any penetrations (like glass door hardware) must be properly sealed. The tile installation over the membrane requires appropriate adhesive and grout, with movement joints sealed using silicone caulk rather than grout.

Given Ottawa's building requirements and the complexity of proper waterproofing, this work is best handled by licensed contractors. Improper waterproofing can lead to expensive water damage in surrounding areas. For a professional assessment of your shower curb waterproofing needs, request a quote from Ottawa Bathrooms - we ensure all waterproofing meets Ontario Building Code requirements and manufacturer specifications.