Tub to Curbless Shower (accessibility)
Tub to curbless shower is the aging-in-place and ADA-accessible conversion — the alcove tub comes out and a zero-threshold walk-in shower goes in with no entry curb at all, a single-plane floor sloped to a linear drain at the back or one side wall, structural blocking installed during framing so ADA-rated grab bars can land anywhere later, an integrated tile bench, and an ADA-compliant single-handle mixer with both a handheld and a fixed shower head. The floor structure gets assessed first — most curbless conversions require the subfloor to be recessed (sometimes a sister-joist) or the surrounding floor built up, so the transition from bath floor to shower floor is truly zero-threshold rather than the cosmetic 1/2-inch "almost curbless" that defeats the wheelchair purpose. Ten to fourteen working days. From $8,000 for a standard ceramic curbless build with a linear drain to $16,000 for the full ADA package with bench, three grab bars, ADA mixer, body sprays, and a frameless glass panel. The in-wall plumbing — drain relocation to the linear position and any valve work — subcontracts to a licensed Washington L&I plumber.
Service
How the Curbless Conversion Works
Six sequential phases from floor structural assessment to ADA fixture trim — the actual working sequence we run on every curbless walk-in conversion, with grab-bar blocking installed during framing for future flexibility.
Floor Structural Assessment + Subfloor Plan
Estimate visit checks the floor structure (joist depth, span, what is below the bath, whether the subfloor can be recessed 1.5 to 2 inches or whether the surrounding floor needs to build up to the shower pan height). We tell you on the estimate which method applies before contract signing. No surprises mid-build about whether curbless is even structurally possible.
Demo + Subfloor Recess (or Build-Up) + Drain Relocation Plumber Visit
Tub demo, surround down to studs, subfloor recess cut and sister-joisted (or surrounding floor framed up to pan height), then the licensed Washington L&I plumber arrives for drain relocation. The original tub drain in the center of the alcove moves to the linear-drain position at the back or side wall. Plumber visit runs 5 to 7 hours on a curbless job — more involved than a center-drain conversion.
Framing with Grab-Bar Blocking at 3 Heights + Linear Drain Channel
Framing closes with 2x6 or 2x8 horizontal blocking at vertical-entry grab bar height, horizontal back-wall grab bar height, and bench-edge bar height — so future grab bars land in solid wood instead of needing rated toggles. Linear drain channel (Schluter Kerdi-Line, Infinity Drain) framed in at the back or one side wall with the waterproof flange ready.
Single-Plane Sloped Pan + Waterproof Membrane + 24-Hour Flood Test
Mortar pan dry-packed in a single plane at 1/4 inch per foot toward the linear drain (geometrically simpler than a four-way center-drain slope). Waterproof membrane installed (sheet Kerdi or rolled RedGard), drain flange embedded, membrane carried up the walls 8 inches and over the bench framing. Pan flood-tests 24 hours with extra attention at the threshold transition.
Slip-Resistant Floor Tile + ADA-Rated Grab Bars Into Blocking
Floor tile is slip-resistant per spec (small-format porcelain mosaic or textured large-format at DCOF 0.42 or higher per ANSI A137.1). Wall tile is large-format porcelain or ceramic at homeowner's selection. ADA-rated stainless grab bars (250-pound per ADA Section 609) install into the blocking from step 3 — typically vertical at the entry, horizontal long-grip on the back wall, angled at the bench edge. Pull-tested with full body weight.
Frameless Glass Panel + ADA Mixer + Handheld + Plumber Final Trim
Fixed frameless 3/8-inch tempered glass panel (single panel, not a hinged door, to keep the entry barrier-free) installed after silicone cures. Licensed plumber returns for ADA-compliant single-handle lever mixer accessible from outside the shower, fixed shower head, handheld on a slide bar so a seated user can shower seated, and any body sprays or rain head if specified. Final walk-through and warranty paperwork hand-off.
Curbless Shower (ADA Accessibility) Pricing
Final pricing depends on the floor structural work required (recess vs build-up), the tile selection, and the ADA scope (grab bar count, bench size, fixture package). The licensed plumber's portion (drain relocation, ADA mixer trim, fixture work) is included in every quote. Plumbing permit, where required by Seattle DCI or your city, also lives inside the project total. Request a free in-home estimate for an accurate quote.
Tell us the bath layout, the floor structure, and the ADA needs — we will quote the curbless project including the plumber's portion.
Why Aging-In-Place Customers Book Handis for Curbless Conversions
A curbless conversion done correctly is a different project from a curbed walk-in — the floor structure is the first question, not the tile selection. Many bathrooms cannot be recessed without sister-joisting (a second-story bath over a finished ceiling space loses too much head room if you just notch the joists; the right answer is sister-joisting from below the basement ceiling). Some baths cannot be curbless at all without raising the surrounding bath floor by an inch and a half — also valid, but a different scope. The other failure mode we see on bad curbless installs is grab-bar blocking missed at framing because the homeowner did not commit to bar positions yet — six months later they want a bar where the tile has to come down because there is no blocking behind it. Handis installs blocking at three heights during framing regardless of whether you have picked bar positions, because the cost of putting blocking in during framing is twenty minutes; the cost of opening tile later is thousands.
Estimate
Tell us the bath layout, the floor structure (second-story over basement, on-slab, etc.), the user's accessibility needs (wheelchair vs walker vs ambulatory with grab bars), the desired grab-bar positions, and any other ADA preferences (comfort-height toilet, additional fixtures). We send back a clear estimate and a project timeline.
Customer Reviews
Tub to curbless shower (ADA accessibility) reviews from real Handis customers.
Curbless ADA conversion for my dad moving in with us. The team assessed the second-story floor first (the bath sits over the kitchen — they sister-joisted from the kitchen ceiling to allow the recess) and installed grab-bar blocking during framing at three heights even though we had only committed to two bars. Single-plane slope to a Schluter Kerdi-Line at the back wall, ADA lever mixer, handheld on a slide bar so dad can shower seated. Twelve working days. The frameless glass panel was the cleanest curbless install I have seen.
We started thinking about aging-in-place after my mom had a fall in her old shower. Booked the curbless build with three grab bars (entry vertical, back-wall horizontal long-grip, bench-edge angled), a 12-inch deep tile bench, comfort-height toilet, and frameless glass. The team built the bench framing inside the waterproof envelope so the bench tile gets the same membrane as the pan — no leak path through the bench seat. Mom has not had a near-miss in two years.
My husband uses a wheelchair part-time after a back surgery. The standard curbless was actually not enough — we needed a wider opening too. Handis widened the entry to 36 inches by re-framing the door wall (we had to give up a closet to do it but it was worth it), installed the linear drain along the back wall, and put grab bars at three positions. The barrier-free transition extends out under the bath floor tile for two feet so a wheelchair rolling out does not catch any edge.
1956 brick rancher in Magnolia, the bath had been re-done in 2003 with a standard tub. We did the curbless conversion with the porcelain large-format walls, slip-resistant porcelain mosaic floor at DCOF 0.51 (the tech actually showed me the spec sheet), and the licensed plumber handled the drain relocation from the original alcove center to the linear position at the back wall. Eleven working days. Permits pulled by the plumber, inspection passed first try.
My in-laws are moving into the in-law unit we built on our property. The curbless conversion was the biggest accessibility upgrade we needed. Handis came in, looked at the on-slab floor, said the recess was not going to work without a major slab cut and recommended the surrounding floor build-up approach instead. Tile floor in the rest of the bath is now 1.5 inches higher than it was, the shower pan sits flush, and the transition is true zero-threshold. They were upfront on the trade-offs at the estimate visit.
Frequently Asked Questions
Common questions about tub to curbless shower (ADA accessibility) conversion — pricing, timeline, floor structure, ADA standards, and what to expect.