Does Shower Tile Need to Be Sealed?
Whether shower tile needs sealing depends on the type of tile and grout. After decades of installing tile showers in Oklahoma homes, we clarify which tiles and grouts need sealing and which do not.
Tile Sealing vs. Grout Sealing
First, understand the distinction:
- Tile sealing — applying sealer to the tile surface to protect the tile material.
- Grout sealing — applying sealer to the grout joints to protect the grout.
These are separate considerations. Some tiles need sealing; some do not. Grout sealing depends on the grout type.
Which Tiles Need Sealing?
Glazed Ceramic and Porcelain Tile
- Sealing needed: No — the glaze is waterproof and non-porous.
- Why: The glaze protects the tile; the tile body does not need sealing.
Most shower tile is glazed ceramic or porcelain. These tiles do not need sealing.
Unglazed Ceramic and Porcelain Tile
- Sealing needed: Yes — unglazed tile is porous.
- Why: Without glaze, the tile body can absorb water and stains.
Unglazed tiles like quarry tile and some porcelain tiles need sealing.
Natural Stone Tile
- Sealing needed: Yes — natural stone is porous.
- Why: Marble, travertine, limestone, slate, and granite are porous and absorb water and stains.
All natural stone tiles used in showers need sealing, including:
- Marble
- Travertine
- Limestone
- Slate
- Granite
- Sandstone
Glass Tile
- Sealing needed: No — glass is non-porous.
- Why: Glass does not absorb water or stains.
Glass tile does not need sealing, but the grout around it may.
Mosaic and Mixed-Material Tile
- Sealing needed: Depends on the materials — seal if natural stone is present.
Comparison: Tile Sealing Requirements
| Tile Type | Needs Sealing? | Why |
|---|---|---|
| Glazed ceramic | No | Glaze is waterproof |
| Glazed porcelain | No | Glaze is waterproof |
| Unglazed ceramic | Yes | Tile body is porous |
| Unglazed porcelain | Yes | Tile body is porous |
| Marble | Yes | Natural stone is porous |
| Travertine | Yes | Natural stone is porous |
| Slate | Yes | Natural stone is porous |
| Glass | No | Glass is non-porous |
Grout Sealing
Grout sealing depends on the grout type:
- Cement grout — yes, requires sealing; porous and susceptible to stains and water.
- Epoxy grout — no, non-porous and waterproof.
- Urethane grout — no, non-porous when cured.
- Single-component grout — check manufacturer specifications; most do not require sealing.
Why Cement Grout Needs Sealing
Cement grout is porous and absorbs:
- Water — leading to mold and deterioration.
- Stains — from soap, shampoo, and minerals.
- Mold and mildew — porous grout supports growth.
- Soap scum — accumulates in porous grout.
Sealing cement grout creates a protective barrier that repels water and stains.
How to Seal Tile and Grout
- Wait for curing — wait 48-72 hours after grout installation before sealing.
- Clean the surface — ensure tile and grout are clean and dry.
- Apply sealer — use a penetrating sealer; apply with a brush, sponge, or applicator.
- Allow penetration — let the sealer penetrate for the manufacturer-specified time.
- Wipe excess — remove excess sealer from tile surfaces.
- Apply second coat — if recommended by the manufacturer.
- Allow curing — wait 24-48 hours before using the shower.
How Often to Seal
- Cement grout in showers — seal annually.
- Natural stone tile — seal annually, or more frequently if the shower is used heavily.
- High-traffic showers — may need sealing every 6 months.
How to Tell If Sealer Is Needed
Test whether sealing is needed with the water drop test:
- Place a few drops of water on the grout or unglazed tile.
- Wait 15 minutes.
- If the water beads up — sealer is still effective.
- If the water absorbs — it is time to reseal.
Choosing a Sealer
- Penetrating sealer — soaks into the material; invisible; does not change appearance.
- Enhancing sealer — deepens the color of natural stone.
- Topical sealer — forms a film on the surface; changes appearance; less breathable.
For showers, use a penetrating sealer — it does not change appearance and allows the material to breathe.
Oklahoma Considerations
Oklahoma's hard water leaves mineral deposits on tile and grout. Sealing grout helps resist mineral buildup and makes cleaning easier. Oklahoma's humid climate also makes mold resistance important — sealing cement grout helps resist mold growth.
Key Takeaways
- Glazed ceramic and porcelain tile do not need sealing — the glaze is waterproof.
- Natural stone tile (marble, travertine, slate) requires sealing — it is porous.
- Cement grout requires sealing; epoxy and urethane grout do not.
- Seal cement grout in showers annually.
- Use a penetrating sealer that does not change appearance.
Common Mistakes to Avoid
- Not sealing cement grout in showers.
- Sealing glazed ceramic or porcelain tile (unnecessary).
- Not sealing natural stone tile.
- Using topical sealers that trap moisture.
- Not resealing cement grout annually.
Questions to Ask Before You Buy
- Does my tile type need sealing?
- Does my grout type need sealing?
- How often should I reseal?
- What type of sealer is best for my shower?
- How can I test if my sealer is still effective?
Maintenance Tips
- Test grout sealer annually with the water drop test.
- Use pH-neutral cleaners; avoid acidic or abrasive cleaners.
- Squeegee the shower after each use to reduce water and mineral buildup.
- Ensure proper ventilation to reduce moisture and mold.
- Address cracked or missing grout promptly.
When to Speak with a Flooring Professional
A tile professional can tell you whether your tile and grout need sealing, recommend the right sealer, and perform the sealing if needed. They can also assess the condition of existing sealer and recommend resealing.
Bottom Line
Glazed ceramic and porcelain tile do not need sealing. Natural stone tile (marble, travertine, slate) requires sealing. Cement grout requires annual sealing; epoxy and urethane grout do not. Use a penetrating sealer, test annually with the water drop test, and reseal as needed. Proper sealing protects your shower from water damage, stains, and mold.
Related Articles
- What Is the Best Grout for a Shower?
- Should You Use Epoxy Grout or Cement Grout?
- Why Does Shower Grout Crack?
- What Is a Waterproof Shower System?
Still have questions? Visit your nearest Premier Carpet & Tile showroom to speak with an experienced flooring professional who can help you plan your project with confidence.
Key considerations
- Glazed ceramic and porcelain tile do not need sealing — the glaze is waterproof
- Natural stone tile (marble, travertine, slate) requires sealing — it is porous
- Cement grout requires sealing; epoxy and urethane grout do not
- Seal cement grout in showers annually
- Use a penetrating sealer that does not change appearance
A common misconception
Many homeowners believe glazed tile does not need sealing because the glaze makes it waterproof. While the tile surface is waterproof, the grout between tiles is porous and requires sealing. Sealing tile and grout are two different considerations.
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