08/10/2026
Your contractor says "we used green board, it's waterproof." Watch why that's wrong. Because green board belongs on the ceiling, and behind your shower tile it's an $18,000 to $27,000 mistake.
Green Board vs. Cement Board: What's Behind Your Tile? Monty | The Builder's Coach explains it.
If your contractor hasn't shown you what's behind your tile, you don't know if your bathroom was waterproofed. Here's the difference most people never learn:
🟩 Green board is moisture-resistant drywall. It belongs on the ceiling and dry walls, not behind tile in a wet area. Soaked over and over, it breaks down and grows mold.
⬜ Cement board (Durock) stays strong when it gets wet. It belongs on every wall where tile meets water, all the way down the wall, before the tile goes on.
Skip it, and the story goes like this: a grout line cracks, water gets behind it, the drywall soaks, the wood rots, and a stain shows up on the ceiling below. Now your remodel gets gutted. That's an $18,000 to $27,000 mistake, paid with your hard-earned money, twice.
Remodeling? Ask your contractor to show you the walls before tile day. Buying a renovated house? Ask the seller for photos of the bathroom before the tile went in.
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