I just finished my second curbless tile shower with a tile-insert linear drain, and the planning for the drain is more involved than people expect. The drain choice affects waterproofing membrane fit, tile thickness range, slope direction, and how the finished shower looks. Here are five drains I either installed or seriously considered, with notes on what they do well.
| Drain | Type | Tile Thickness | Flange | Best For |
|---|---|---|---|---|
| Schluter Kerdi-Line | Linear | 3/8 to 5/8 in | Integrated | Schluter waterproofing systems |
| KBRS Linear | Linear | 1/4 to 3/4 in | PVC | Pan-and-curb conversions |
| Infinity Drain LT | Linear | 3/8 to 3/4 in | Stainless | High-end remodels |
| Quick Drain ProLine | Linear | 3/8 to 5/8 in | Stainless | Pro installs |
| Tile Redi Square | Center | 3/8 to 1/2 in | Integrated | Drop-in showers |
Schluter Kerdi-Line
The Schluter Kerdi-Line is the drain I used on my last build because it integrates directly with the Kerdi waterproofing membrane. The flange has the membrane bonded right to it, so the seam at the drain isn’t a weak point. Tile insert is anchored cleanly and ships with adjustable height. Flow rate handles a typical shower without standing water. The drain body fits standard 2-inch PVC. The trade-off is the price; it’s at the higher end. If you’re using Schluter membrane already, the system fit is worth it.
KBRS Linear
The KBRS Linear drain is the value pick for tile-insert builds. PVC flange that accepts a wide range of waterproofing methods including hot-mop, sheet membrane, and liquid. The insert tray accepts tile up to 3/4 inch, which covers thick natural stone better than most. Drain pan is roughly half the price of the Schluter. The downside is the install steps are slightly less idiot-proof; the membrane-to-flange seal requires careful clamping. For competent DIYers it’s a strong pick.
Infinity Drain LT
The Infinity Drain LT is the high-end pick I’d specify for a master bath where details matter. 304 stainless body, custom tile insert tray that can be ordered to length, and a flange that works with most major waterproofing systems. The frame is thicker and the fit between insert and frame is tighter than the others I compared, so the tile sits flush with no reveal. Flow rate is the highest in this group, which matters for body-spray showers. It’s the most expensive option, and lead time can be a few weeks.
Quick Drain ProLine
The Quick Drain ProLine is the drain pros tend to default to because it has a wide range of widths and an established install procedure. Stainless body and tile insert, integrated waterproofing flange, and a removable insert for cleaning out hair and gunk. Flow rate is rated for high-flow showers. The frame tolerances are tight and the insert sits very flush. Pricier than Schluter but with broader sizing options. Long warranty terms.
Tile Redi Square
The Tile Redi Square is the center-drain pick for people who don’t want a linear drain. It comes integrated with a sloped shower pan, which simplifies the build significantly because you don’t have to mud-pack a slope. Tile insert sits flush with the surrounding tile. Best for showers where you can use small tiles or mosaics around the drain to follow the four-way slope. Not appropriate for big-format tile. The pan-plus-drain combo is competitive with buying components separately.
What Matters Most
Match the drain to your waterproofing system. A drain with an integrated membrane flange like Schluter cuts out a major failure point. Tile thickness range matters because natural stone runs thick. Length of linear drain controls where you can place it relative to the bench and door; standard is 24, 32, or 36 inches. Flow rate matters for body-spray or rainhead showers. Insert removability for cleaning is something you’ll appreciate every few months when hair builds up.
My Setup
In my main bath I used a 32-inch Schluter Kerdi-Line set against the back wall, with the floor sloped one direction toward it. 12 by 24 inch porcelain tile runs flat across the slope. Below the drain I used a standard 2-inch P-trap and ABS to the existing branch line. Floor membrane is Kerdi sheet, mortared over a 1.5 percent slope. Around the drain I dry-fit the insert before grouting to make sure the tile reveal was even.
Common Mistakes
Skipping the test fit before final tile install creates uneven reveal around the insert tray, which is the most visible flaw in the finished work. Not sloping the floor enough toward the drain causes standing water; aim for at least 1/4 inch per foot. Sealing the membrane to the flange with the wrong adhesive voids most warranties. Cutting tile to fit the insert with the wrong blade chips the edges. Forgetting the trap primer on a drain that doesn’t see regular use leads to sewer gas seeping out.
Final Recommendation
For most curbless tile showers built with Schluter membrane, the Schluter Kerdi-Line is the right pick because system fit eliminates a leak point. For other waterproofing methods or tighter budgets, the KBRS Linear is the value play. Specify the Infinity Drain LT or Quick Drain ProLine for higher-end builds where finish details matter and budget allows. For drop-in remodels where you don’t want to build a sloped mud bed, the Tile Redi Square is the path of least resistance. Plan your slope direction before ordering anything.
Frequently asked questions
Linear drain or center drain for a tile shower?+
Linear drains let you slope the floor in one direction, which lets you use bigger tile and creates a cleaner look. Center drains need a four-way slope and only work with small tiles or mosaics.
Do tile-insert drains drain slower than open grates?+
Slightly, because water has to flow around the tile to the perimeter slots. With proper slope, the difference doesn't matter for normal shower flow rates.
Can I install a tile-insert drain in a wood-framed floor?+
Yes, but you need to recess the joists or build a sloped subfloor to get the drain low enough. Most retrofit jobs require structural work and a licensed plumber for the trap connection.