Hide Bathtub Tile Edges (Schluter Edge Trim)
To finish an exposed bathtub-surround tile edge, choose a Schluter profile sized for the tile and setting assembly, then install it as part of the tile work. The profile gives the edge a clean finish, but it does not replace waterproofing. Keep the membrane continuous, and leave the tub-to-tile joint flexible with compatible sealant.
A neat tile edge helps a bathroom feel calm and complete. A rough cut, exposed tile body, or uneven line can catch your eye every time you use the tub. The fix is not simply to cover the edge with metal. The profile, tile, waterproofing, and tub joint must work as one assembly.
I treat the edge as a small detail with several jobs: protect the tile, create a straight finish, and preserve the water-control system behind it. The steps below help you plan that detail before mortar is mixed.
Plan the Edge Finish and Confirm the Governing Requirements
A Schluter edge profile is a shaped trim with a perforated anchoring leg that is set into tile mortar. Its visible face finishes and protects an exposed tile edge. It is not a waterproofing layer, so the membrane behind the tile must do that job.
First, identify where the tile ends. A profile may finish a vertical outside edge, a short return, or another exposed boundary. Check that the trim will cover the cut edge and meet nearby surfaces without interfering with the tub rim or fixtures.
Then check the rules that apply to your project. IRC P2708.2, where adopted and applicable, requires a nonabsorbent finish at a bathtub with a shower to extend at least 6 ft (1829 mm) above the floor. Confirm your local code edition and how it applies to the work. The profile itself does not establish compliance.
For the tile assembly, use a bonded waterproof membrane listed to ANSI A118.10 when that is the selected system, and follow its manufacturer’s installation instructions. The tile, mortar, profile, and membrane instructions all matter. If the instructions differ from a general example, follow the product requirements and local code.
Before ordering, record:
- The tile’s actual thickness, not just its nominal size.
- The exposed edge length and whether it is straight or angled.
- The tub rim and flange shape.
- The waterproofing method and where it continues around the edge.
- The exact profile model and its current sizing chart.
Next step: Choose a specific profile only after you know the tile and setting assembly.
Check Tile, Tub, Substrate, and Profile Clearances
A good fit depends on the full installed assembly, not on tile thickness alone. Mortar under the tile adds height, while the profile’s shape and depth affect how the tile edge meets its visible face. Check these parts together before setting.
Schluter profile heights vary by product. Use the sizing chart for the exact profile you plan to install, and compare it with the tile thickness and specified setting material. Do not choose a height by appearance or assume one model’s sizing applies to another.
| Check | What to look for | Why it matters |
|---|---|---|
| Tile edge | Chips, uneven cuts, and actual thickness | The profile must cover the edge and sit as intended |
| Tub geometry | Rim, flange, and clearance at the tile line | Trim must not bind on the tub or block the joint |
| Substrate | Firm, sound, and flat surface | An uneven base can make the profile and tile wavy |
| Waterproofing | Membrane location and continuity | Trim cannot correct a gap in water protection |
| Profile size | Product chart and full setting assembly | A mismatch can leave the tile proud or recessed |
Check flatness before tile setting. Under ANSI A108.02, for tile with all edges under 15 in., the maximum substrate variation is 1/4 in. in 10 ft and 1/16 in. in 1 ft. Large-format tile has tighter requirements; confirm the applicable standard and requirements for your tile dimensions.
Also check whether the profile’s anchoring leg can be embedded in the specified setting material without disrupting the waterproofing detail. The correct order can depend on the membrane and profile system. Do not cut, puncture, or cover a membrane in a way that conflicts with its instructions.
Next step: Dry-check the profile and tile against the tub before committing to mortar.
Install the Profile Without Breaking Waterproofing
The profile is installed with its anchoring leg embedded in the specified setting material, then aligned with the tile edge. The exact orientation, mortar coverage, and relationship to waterproofing vary by product. Follow the current instructions for the selected Schluter profile and membrane.
Prepare and inspect. Confirm the substrate is sound and flat, the tile fits, and the waterproofing is in place as specified. Remove dust and debris. Check that the cut edge is not so damaged that the trim cannot cover it cleanly.
Mark the finish line. Use a level or straightedge to mark where the visible profile face will sit. Check the line from the tub to the top of the tiled area. A slight error can become more noticeable across a long vertical edge.
Set the profile. Apply the specified mortar and press the anchoring leg into it as directed by the product instructions. Align the profile, then remove excess mortar from areas where it could interfere with the tile or joint. Do not force the profile against the tub.
Set the tile. Place the tile beside the profile in the position the product detail calls for. Maintain the intended joint between tile and trim. Check the face of the tile against the profile as you work so the edge does not end up proud or recessed.
Complete the finish. Use grout or sealant at the tile-to-profile joint only as the profile instructions allow. Keep mortar and grout out of the tub-to-tile movement joint.
The profile leg may be part of a manufacturer-approved waterproofing detail, but it is not a substitute for the membrane. If the leg’s placement would interrupt or damage the waterproofing, stop and resolve the detail before tiling. Do not assume that metal trim seals a cut tile edge or a membrane gap.
Next step: Let materials cure as directed, then inspect the edge and the tub joint before use.
Verify the Finish, Movement Joint, and Water Protection
A finished edge should be straight, secure, and free of sharp or exposed tile edges. The nearby tub joint must still allow movement. Inspect both details after installation; a clean-looking trim line does not prove that the waterproofing is continuous.
The tub-to-tile change of plane is a movement joint. Follow TCNA EJ171 and the sealant and membrane manufacturers’ instructions for its placement and treatment. Use a compatible flexible sealant rather than rigid grout at that joint. Its width depends on the assembly, so there is no single dimension that suits every tub and tile installation.
Inspect for:
- A loose, twisted, or visibly wavy profile.
- Tile edges that the profile does not cover.
- Voids or gaps along the profile and tile.
- Cracked grout or grout bridging the tub joint.
- A movement joint that is blocked, unsealed, or filled with rigid material.
- Any sign that the membrane was cut or left discontinuous.
If you find a problem with membrane continuity, address it according to the membrane system’s repair instructions before the area is put into service. Adding sealant over a visible trim edge is not a reliable fix for a hidden waterproofing defect.
Key check: The profile finishes the edge; the membrane protects the assembly, and the flexible joint accommodates movement.
Two Common Bathtub Edge Scenarios
These examples show how the same trim decision changes with the site. They are practical scenarios, not a substitute for the instructions for your exact tile, profile, or waterproofing system.
Scenario 1: A straight, exposed vertical edge. A homeowner has a full-height tiled surround that ends beside painted drywall. The tile edge is sound, and the selected profile’s sizing chart matches the tile and setting assembly. The installer checks the line with a straightedge, embeds the anchoring leg as directed, and keeps the waterproofing continuous behind the tile. The tub joint remains a separate flexible sealant joint.
Scenario 2: A tight tub-rim clearance. At another surround, the proposed profile appears to touch the tub when held in place. Rather than forcing it or choosing a thinner profile by eye, the installer checks the profile drawing, tile thickness, and tub geometry. If the selected detail cannot fit while preserving the movement joint, the edge detail must be revised before tile is set.
In both cases, the important decision happens before installation: verify fit and water protection together, not as separate tasks.
Conclusion: Choose the Profile as Part of the Assembly
A well-chosen Schluter profile can make a bathtub tile edge look crisp and protect the tile’s exposed side. The right height comes from the specific product chart and the full setting assembly, while the waterproofing and tub movement joint need their own correct details.
Before work begins, confirm local code, tile and substrate conditions, profile instructions, membrane continuity, and tub clearance. After installation, check the trim line and keep the tub-to-tile joint flexible.
Frequently Asked Questions
These quick answers cover common questions about finishing bathtub-surround tile edges. Product details can vary, so confirm the current instructions for your profile, tile, membrane, and sealant before installation.
Can Schluter trim hide an exposed bathtub tile edge?
Yes. A suitable profile can cover and finish an exposed tile edge. Select its height for the actual tile and setting assembly, and follow the product’s installation instructions.
Does Schluter trim waterproof a bathtub surround?
No. The profile is an edge finish, not a waterproofing substitute. The membrane behind the tile must remain continuous and be installed as its manufacturer directs.
How do I choose the right profile height?
Measure the tile and check the sizing chart for the exact profile. Account for the specified setting assembly; do not select a height by appearance alone.
Can I install trim over a finished tile edge?
Usually, the anchoring leg is designed to be embedded during tile setting. Whether a particular profile can be added later depends on that product’s design and instructions.
Should I grout the joint between the tub and tile?
No. Treat this change of plane as a movement joint and use compatible flexible sealant, following TCNA EJ171 and the product instructions.
Can I grout between the tile and the profile?
That depends on the profile detail. Use grout or sealant only as directed for the specific profile and setting system.
What if the profile sits higher than the tile?
Stop and check the tile thickness, setting assembly, and profile sizing. Do not force the tile or rely on extra grout to hide a mismatch.
What if the tub is not level?
Check the tub and tile layout before setting the profile. A sloped or uneven rim can affect the joint and visual line; resolve the layout and clearance rather than binding trim against the tub.
How high must the tiled finish extend?
Where locally adopted IRC P2708.2 applies to a bathtub with a shower, the nonabsorbent finish extends at least 6 ft (1829 mm) above the floor. Confirm local code scope and edition.
Can I repair a broken waterproofing layer with metal trim?
No. Trim does not repair a discontinuous membrane. Use the membrane manufacturer’s approved repair method before closing the assembly.
(This article was written by one of our staff writers, Michael Donovan. Visit our Meet the Team page.)
