The days of waiting for water from your shower or tub to leak behind your walls are far behind us. Bathroom remodeling now uses proactive materials that prevent the once “inevitable” rotten wood, mold, and mildew that lurk behind old shower walls. Stagnant water is a prime driver of growth for Aspergillus, Cladosporium, Penicillium, and Stachybotrys (black mold). You’ll often first notice greenish-to-black discoloration along the base of a shower or tub—where water can pool and sit.
Modern Waterproofing That Works
Tile + Schluter®-KERDI vs. Solid Surface Walls
Many grout lines; periodic care
Virtually seamless; no grout lines
Continuous sheet membrane behind tile
Non-porous panels; sealed seams are the waterproof layer
Grout sealing/refresh; mildew vigilance
Wipe with mild soap; very low effort
Longer (layout, set, grout, cure)
Faster (large panels, fewer steps)
Tile replacement; color/lot match can show
Panels can be refinished or section-replaced
Unlimited tile patterns & layouts
Modern stone/tile looks; clean lines
Higher upkeep over time (grout)
Lower upkeep; fewer callbacks
Design-forward, custom patterns
Low-maintenance, contemporary look
Schluter®-KERDI for Tile Lovers
If you prefer classic tile, the Schluter system has become a go-to waterproofing barrier in the South (it’s been popular up North for years). Schluter®-KERDI is a sheet membrane applied between backer board and tile—or used as the backer itself. It’s impenetrable to water and comes with pre-formed pieces for corners, seams, edges, and valve/trim penetrations, creating a continuous waterproof envelope behind your tile.
Solid Surface & Acrylic Wall Systems (No Grout Lines)
One of the fastest-growing trends is solid surface shower walls—either natural stone that’s surface-sealed or synthetic (acrylic/engineered) panels that are 100% waterproof by design. Large, single sheets minimize seams and eliminate grout lines. Explore low-maintenance options like the Onyx Collection, which can mimic tile or natural stone without the upkeep.
Don’t Forget the Base (Pan) — Where Drainage Starts
Your waterproofing is only as good as your base. For tile builds, pre-sloped Schluter pans keep water moving to the drain and pair with the membrane for a complete system. For solid-surface setups, ONYX bases are fully waterproof, custom-sized, available in multiple threshold heights, and backed by a lifetime warranty. Factory pre-slope ensures water doesn’t linger after each use.
Best Practices to Prevent Mold & Mildew
- Continuous waterproofing: Use a single, compatible system from walls to pan.
- Pre-slope & correct drain sizing: Showers typically need a 2″ drain; slope prevents standing water.
- Seam control: Minimize seams; seal all transitions (wall-to-pan, panel-to-panel) with approved sealants.
- Ventilation: A properly sized exhaust fan reduces humidity that fuels mold growth.
- Material choice: Prefer non-porous surfaces (solid surface/acrylic) or fully membrane-backed tile.
Tile or Solid Surface — Choose What Fits Your Life
Tile offers limitless design—but requires grout care. Solid surface panels deliver a clean, modern look with near-zero maintenance. Either route can be built to last when installed correctly. If you want help weighing options for your layout, budget, and maintenance goals, start with a quick plan for a shower remodel from a local bathroom remodeling company you can trust.
FAQ: Waterproof Showers & Mold Prevention
Q: Do I need both a membrane and backer board behind tile?
A: Yes—use a compatible substrate and a continuous waterproof membrane (e.g., Schluter®-KERDI) for a fully sealed system.
Q: Can solid surface panels go over existing tile?
A: Often, yes—if the tile is sound, flat, and properly bonded. A pro will verify substrate condition and clearances first.
Q: What’s the lowest-maintenance wall option?
A: Solid surface/acrylic panels—no grout lines, simple wipe-downs, and excellent water resistance.
Q: How do I keep mold from returning?
A: Ensure proper slope/drain sizing, continuous waterproofing, and adequate ventilation. Wipe down surfaces after use to reduce standing water.
Q: Will a custom base fit my non-standard shower?
A: Yes—ONYX and similar systems are templated to your exact footprint and threshold height, then factory pre-sloped for correct drainage.