SEMCO field notes
bathroom guides.
Prep, application and troubleshooting for basements, roofs, showers, pools and more, written by the team that makes SEMCO.
5 articles
bathroomWhat Does It Cost to Waterproof a Shower Before Tiling? 2026 DIY vs Pro Breakdown
Professional shower waterproofing runs $450 to $2,500 depending on scope. A DIY liquid membrane and fabric reinforcement costs about $150 to $200...
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bathroomShower Waterproofing Membrane: What Actually Stops Leaks Behind the Tile
Grout isn't what stops a shower leak. See the 3 spots where showers actually fail, and how to waterproof them with a...
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bathroomWater-Based Membrane vs Silicone-Based Coating: Which Belongs in a Shower
Silicone-based coatings and a water-based liquid membrane both waterproof a shower before tile. Here's how they compare, by scenario, cure time, and...
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basementDo You Really Need to Waterproof Drywall? Every Question Answered
Is drywall really waterproof? Get straight answers on green board, cement board, and how to seal drywall seams yourself with a water-based...
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bathroomShower Waterproofing Membrane: The Complete DIY Guide Before Tiling
Tile and grout aren't waterproof on their own. Here's how to waterproof a shower before tiling with a DIY liquid membrane, seam...
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