Curbless Showers: The Modern Bathroom Trend That's Here to Stay

Curbless showers — also called zero-threshold, barrier-free, or walk-in showers — have moved from niche accessibility feature to mainstream design statement. The clean, seamless transition from bathroom floor to shower floor creates a spa-like openness that transforms the entire room. But building a curbless shower correctly requires specific engineering, materials, and expertise that not every contractor can deliver.

How a Curbless Shower Works

A traditional shower has a curb (the raised ledge at the entrance) that contains water inside the shower enclosure. Remove that curb and you need an alternative system to manage water flow. The solution combines three engineering elements:

1. Precision Floor Slope

The entire shower floor must slope toward the drain at a minimum pitch of 1/4 inch per linear foot. In a traditional curbed shower, only the shower pan needs to slope. In a curbless design, the slope often extends slightly beyond the shower footprint to prevent water from flowing into the bathroom.

This slope must be built into the substrate (the mortar bed or foam shower tray) with millimeter precision. Too little slope and water pools. Too much slope and the floor feels uncomfortable underfoot and can create a tripping hazard — defeating the purpose of going curbless.

2. Linear Drain Systems

Traditional center-point drains work with small mosaic tiles that can conform to a four-way slope. Curbless showers typically use linear drains positioned along one wall (usually the back wall or the entrance side). Linear drains offer several advantages:

• •Single-direction slope: The floor only needs to slope in one direction toward the linear drain, rather than four directions toward a center point. This allows the use of larger floor tiles.
• •Higher flow capacity: Linear drains handle more gallons per minute than standard point drains, reducing the risk of water escaping the shower area.
• •Design integration: Modern linear drains come with tile-in grate options that make the drain nearly invisible, or decorative metal grates in matching hardware finishes.

Showerly includes a linear drain add-on for $450, or it's included in our Masterpiece package.

3. Extended Waterproofing

In a curbed shower, the waterproofing membrane needs to cover the shower walls and pan. In a curbless design, the waterproofing must extend beyond the shower footprint — typically 3-6 inches past the transition point — to handle any water that migrates outward before reaching the drain.

We use the full Schluter KERDI system with KERDI-LINE (linear drain integration) and extended KERDI-BAND at all transitions. This creates a continuous waterproof envelope that handles the expanded wet zone of a curbless design.

Waterproofing Challenges Unique to Curbless Showers

Curbless showers present waterproofing scenarios that don't exist in traditional builds:

The Transition Zone

Where the shower floor meets the bathroom floor is the most critical point. Without a curb acting as a physical water barrier, this transition relies entirely on proper slope and waterproofing continuity. The KERDI membrane must bridge this transition seamlessly, with no gaps or unsealed joints.

Floor Height Coordination

The shower floor in a curbless design sits at the same level as (or slightly below) the bathroom floor. This means the drain, slope substrate, tile, and thin-set must all fit within the available floor depth. In some homes — particularly those with slab foundations — this requires recessing the drain into the concrete, which adds complexity and cost.

In homes with raised subfloors (common in Raleigh-area construction over crawl spaces), there's usually sufficient depth to accommodate the slope and drain without structural modifications.

Splash Management Without Glass

Some homeowners envision a completely open curbless shower with no glass at all — the "wet room" concept. While visually stunning, this design requires the entire bathroom floor to be waterproofed and sloped, and it demands careful fixture placement to minimize splash. Most curbless installations benefit from at least a fixed glass panel to contain the primary splash zone while maintaining the open feel.

ADA Compliance and Aging-in-Place Benefits

Curbless showers aren't just a design trend — they're a practical investment in long-term livability.

ADA Requirements Met

The Americans with Disabilities Act (ADA) specifies that accessible showers must have:

• •Zero threshold entry: No curb or lip higher than 1/2 inch
• •Minimum 36×36 inch clear floor space (60×30 inches for transfer-type showers)
• •Grab bars: Mounted at specified heights and locations
• •Accessible controls: Operable with one hand and within reach range

A properly built curbless shower meets the threshold and floor space requirements automatically. Adding grab bars and accessible controls completes the accessibility picture.

Who Benefits Most

• •Aging-in-place homeowners: Eliminating the step-over reduces fall risk, the #1 cause of injury in older adults. A curbless shower installed now avoids a costly emergency remodel later.
• •Families with young children: No curb to trip over when helping small children bathe.
• •Wheelchair users or mobility-aid users: Roll-in access without transfer or assist devices.
• •Anyone recovering from surgery or injury: Temporary mobility limitations become much easier to manage.
• •Multi-generational households: A curbless shower serves every family member safely, regardless of age or ability.

Cost Considerations

Curbless showers cost more than traditional curbed designs due to the additional engineering and materials:

What Adds Cost

• •Linear drain: $450 add-on (included in Masterpiece)
• •Extended waterproofing: Additional KERDI membrane and installation labor
• •Precision slope work: More time-intensive substrate preparation
• •Possible structural modifications: Recessing the drain into concrete slabs or modifying subfloor framing

Showerly's Curbless Add-On

We offer curbless conversion as a $1,200 add-on to any of our shower packages. This includes:

• •Linear drain supply and installation
• •Extended Schluter KERDI waterproofing
• •Precision slope engineering
• •Transition detailing between shower and bathroom floor

Combined with our Essential package, a curbless shower starts at $7,200 ($6,000 + $1,200 curbless). With our Signature package, it's $10,200. These are published, scope-locked prices — no surprise change orders.

Design Considerations for Curbless Showers

Tile Selection

Curbless floors need tiles with excellent slip resistance. We recommend tiles with a DCOF (Dynamic Coefficient of Friction) of 0.50 or higher — above the ADA minimum of 0.42. Mosaic tiles (2×2 or hex) remain ideal for curbless shower floors because the additional grout lines provide traction.

With a linear drain, larger floor tiles (up to 12×24) become possible on the shower floor since the slope runs in a single direction. This creates a cohesive look where the bathroom floor tile can extend seamlessly into the shower.

Glass Options

Curbless showers pair beautifully with frameless glass because the design already eliminates visual barriers. A single fixed glass panel (rather than a full enclosure with a door) maintains the open feel while managing splash. For a true wet-room aesthetic, the glass can be eliminated entirely if the bathroom is designed for it.

Bathroom Floor Integration

The most visually impactful curbless designs use the same tile on both the bathroom floor and the shower floor, creating a seamless visual flow. This requires careful planning of tile layout, drain positioning, and slope to ensure the transition is invisible.

Curious whether a curbless shower would work in your bathroom? Book a free design consult and we'll evaluate your space, discuss the engineering requirements, and provide exact pricing. You can also browse curbless shower projects in our gallery or call (984) 895-0101. Check our FAQs for answers to common curbless shower questions.