Grout that keeps darkening, caulk that won’t stay white, a tile that sounds hollow when you tap it, a musty smell after every shower: these are signs that water is getting past the surface. Re-grouting can hide the symptoms for a while. The fix that lasts is in the layers behind the tile.

Tile and grout are not the waterproof layer

Tile sheds most water, but grout is porous, and some water reaches the layer behind it every time you shower. In a well-built shower that water meets a waterproof layer and drains away. In an older or poorly built one, it soaks into drywall, wood framing or the subfloor. Staining on a ceiling below, a damp baseboard outside the shower or loose floor tiles near the curb all point the same direction.

That’s why cracked grout in the inside corners or a tile that moves under your hand deserves attention. Corners and other changes of plane should get a flexible sealant joint instead of grout, because rigid grout cracks there as the house moves.

What belongs behind the tile

The shower pan

The traditional method is a mortar bed sloped toward the drain, a waterproof liner clamped into the drain, and a second mortar bed on top. California’s plumbing code requires a shower pan built on site to be filled with water and tested before tile goes on, so leaks show up while they’re easy to fix.

Bonded membranes

Newer systems put the waterproofing directly under the tile: a sheet or liquid-applied membrane over the walls and floor, tied into a drain with a bonding flange. Products meeting ANSI A118.10, the industry standard for waterproof membranes under tile, keep water near the surface instead of letting it soak into a mortar bed.

The walls

Cement backer board tolerates water but isn’t waterproof, so it needs a membrane on its face or a moisture barrier behind it, depending on the method. Drywall, including the moisture-resistant kind, doesn’t belong in the wet area of a shower.

Every opening

Niches, benches and valve openings are common weak points. A niche needs waterproofing wrapped into every inside corner and a sill that slopes back toward the shower, a bench needs the same slope on its seat, and pipe openings get sealed to the membrane.

Older showers around Fresno

Census Bureau estimates put roughly half of Fresno’s housing in the pre-1980 range. Showers from that era were often built with tile set in a thick mortar bed over metal lath and building paper. Many have held up well; others have liners that failed long ago or framing that has been damp for a long time.

There’s no way to know from the surface. Demolition exposes the framing, the pan and the drain, and any damage is reviewed with you before new waterproofing goes on. A musty smell that won’t go away is also a ventilation question, and our guide to bathroom ventilation and moisture explains how to clear steam properly.

Choosing tile for walls and floors

The Tile Council of North America defines porcelain as tile with water absorption of 0.5 percent or less, which makes it dense and well suited to floors and wet areas. Glazed ceramic is softer, easier to cut and a good fit on shower walls. Natural stone such as marble needs sealing and gentle cleaners, because acidic products etch it.

Large tiles mean fewer grout lines, but tiles with any edge 15 inches or longer need a flatter surface behind them, and on a shower floor they’re far easier to set with a single-direction slope toward a linear drain. Small mosaics follow a sloped floor easily, and the extra grout lines add grip. Our curbless vs standard shower guide explains how drains and entries shape the floor.

Cement grout is the standard choice and benefits from sealing. Epoxy grout resists stains and doesn’t need sealing, but it’s harder to install and costs more. Rectified tile, with precisely cut edges, allows narrower joints.

Layout and edges matter as much as the tile itself. Long rectangular tiles are usually offset by a third rather than by half, because a slight bow in each tile shows up as uneven edges at the midpoint. Exposed edges at niches and outside corners get bullnose tile or a metal edge profile instead of a raw cut.

Where tile shows up in your range

The estimator’s tile question has two answers: “Standard Tile & Flooring” for quality ceramic and porcelain, and “Custom / Specialty Tile” for handcrafted, imported, natural stone and specialty tile. On the shower question, a rebuilt tiled shower is usually “Custom Tile Shower,” while swapping in a standard shower where the old one stood is “Standard Replacement.” Start in the bathroom estimator to see how those answers shape your range.

Shower rebuilds are rarely stand-alone, since the floor, glass and fixtures around them usually change too. As a planning reference for whole bathrooms, projects begin around $15,000 and a typical remodel comes in around $25,000. Specialty tile, intricate patterns and hidden water damage move a range upward because they take more material and labor. If you’re weighing tile against an acrylic or solid-surface system, our tile vs acrylic showers comparison covers upkeep.

The order of work

After the consultation confirms scope and permit needs, the shower comes down to the studs and subfloor. The drain and valve are set, the floor is sloped, and the waterproofing goes on and is tested before tile starts. Grout cures before it’s sealed, and glass is fitted at the end.

If water damage has spread under the bathroom floor or into the next room, or you want a larger shower or a new drain location, the project grows past a shower rebuild. That’s when it makes sense to plan a walk-in shower or look at a whole bathroom remodel.