Materials
Chosen by the number, then by how it looks
Tile showrooms are lit to make surfaces glow and laid out so you touch them with a dry hand. Almost every dangerous bathroom floor we have pulled up was chosen under exactly those conditions.
- Shower floor DCOF
- 0.62
- Bar load rating
- 250 lbf
- Seat rating
- 400 lb
- Faucet force
- 5 lbf max
Three ratings, and what each one measures
Wet DCOF, the barefoot ramp class and the R-value. They are not interchangeable, and only one of them describes a shower honestly.
DCOF AcuTest
Wet dynamic coefficient of friction, ANSI A137.1. Simulates a shod foot already moving. 0.42 is the published minimum for level interior tile walked on wet. We treat it as a floor.
DIN 51097
The barefoot ramp test, graded A, B or C on a wet soapy incline. The only test that describes a shower honestly, because nobody showers in shoes. We want class B or better.
DIN 51130 R-value
The shod ramp test, R9 to R13, common on imported datasheets. Useful as a cross-check when a DCOF figure is not published. R10 or better for a wet floor.
| Surface | Wet DCOF | DIN 51097 | R-value | Where we use it |
|---|---|---|---|---|
| 2 x 2 in unglazed porcelain mosaic | 0.62 | Class C | R11 | Curbless shower floors. Our default |
| 1 x 1 in porcelain penny round | 0.58 | Class B | R10 | Shower floors where a tighter grout grid is wanted |
| Textured 12 x 24 in porcelain plank | 0.51 | Class B | R10 | Wet bathroom floors outside the shower |
| Honed marble, 12 x 12 in | 0.43 | Class A | R9 | Dry areas only. Never a shower floor |
| Flamed granite, 12 x 12 in | 0.67 | Class C | R11 | Shower floors and thresholds where stone is wanted |
| Polished porcelain, 24 x 24 in | 0.28 | Not rated | R9 | We do not install this in a bathroom |
| Cast acrylic shower pan, textured | 0.55 | Class B | R10 | Tub-to-shower conversions on a budget |
| Sealed sheet vinyl, safety grade | 0.60 | Class C | R10 | Whole-floor option when tile weight is a concern |
Swipe the table sideways to see every column.
Tile size does as much work as the surface. A 2 in mosaic puts a grout joint under the ball of your foot every two inches, and that joint is what a wet foot actually grips. A 24 in plank can carry a good face rating and still feel skittish, which is why our shower pans are always 2 in or smaller.
Wet-area tile
Chosen by measured wet DCOF first. Every tile we carry for a shower floor sits above the ANSI A137.1 minimum of 0.42, most of them well above it.
Unglazed porcelain mosaic, 2 x 2 in
DCOF 0.62 wet, R11, DIN class COur default shower floor. Grout joint every two inches is the grip.
Porcelain penny round, 1 in
DCOF 0.58 wet, R10, DIN class BTighter joint grid where a finer look is wanted. Slightly harder to keep clean.
Textured porcelain plank, 12 x 24 in
DCOF 0.51 wet, R10Wet floor outside the shower. Reads as wood or stone without the risk.
Large-format wall porcelain, 12 x 36 in
Wall rated, not floor ratedWalls only. Fewer joints means less grout to scrub at shoulder height.
Natural stone
Stone belongs in a bathroom, but not everywhere in one. The finish matters more than the species.
Flamed granite, 12 x 12 in
DCOF 0.67 wet, R11The only stone we will lay on a shower floor. Thermal finish, not polish.
Honed marble, walls and vanity
DCOF 0.43, dry areas onlyBeautiful, and fine anywhere that does not get walked on wet.
Quartz vanity top
34 in rim height standardNon-porous, no sealing, forgiving of the products people actually use.
Solid-surface shower panel
Joint-free, 1/2 in thickSeamless walls for a fast conversion. Warm to touch, no grout to maintain.
Glass and enclosures
In an accessible shower, less glass is usually better. A door swing eats the clear opening and a caregiver needs room to reach in.
Single fixed panel, 3/8 in
Tempered, low-iron, clear-coatedOur default. Keeps a 36 in clear opening with no swing at all.
Half-height splash panel
Tempered, 42 in highWhere a full panel would feel closed in. Enough to keep the floor dry.
Weighted fabric curtain track
Ceiling track, 72 in dropThe most caregiver-friendly option. Pushes fully clear in a second.
No enclosure at all
Requires 1/4 in per ft fallA correctly sloped pan and a well-placed head often need nothing.
Grab bars and seats
This is where most bathrooms give themselves away as medical. It does not have to be that way: matched finishes read as hardware.
Knurled stainless bar, 1.25 in
250 lbf rated, ASTM F446The best grip for a wet hand. Available brushed to match the faucet.
Smooth bar with towel shelf
250 lbf rated, 24 or 42 inReads as a towel rail, works as a grab bar. The one people ask for.
Folding shower seat
400 lb static rating16 in deep, folds to 3.5 in so a standing shower is unaffected.
Slide bar with handheld
24 to 30 in bar, 59 in hoseRated as a vertical bar, not a decorative rail. Blocking behind it.
Fixtures and valves
Every fixture we specify is chosen for the force needed to operate it and the height it sits at, then for how it looks.
Thermostatic mixing valve
ASSE 1016, capped 120 FHolds temperature when a toilet flushes. Stop set at the valve.
Comfort-height elongated toilet
17 to 19 in seat heightTwo inches higher than standard. The difference between rising and being lifted.
Single-lever or touchless faucet
5 lbf maximum to operateNo grasping, pinching or twisting. Lever at least 4 in long.
Humidity-sensing exhaust fan
80 to 110 CFM, 1.0 soneRuns on moisture, not on the light switch. Ducted outside, never to the attic.
What to ask any bathroom contractor
- What is the measured wet DCOF of the tile you are putting in my shower pan? A shrug is an answer.
- What size is that pan tile? Anything above 2 in gives a wet foot less to grip, whatever the face rating says.
- What blocking goes in, at what height, and will you pull-test the bars in front of me?
- Is the mixing valve thermostatic or pressure-balancing, and where is the temperature stop set?
- How much fall is in the pan, and does it all happen inside the shower?
- Will you flood-test the membrane for 24 hours before tiling, and will you photograph it?
The last thing on this page
Ninety minutes, at your house, for nothing
Joaquin measures the room against every clearance, maps the studs so we know where blocking can go, and leaves a written report. If the honest answer is that your bathroom cannot do what you need, he will say so and the report is still yours.
- Call
- (941) 555-0213
- Office hours
- Monday to Friday: 7:30 am to 5:30 pmSaturday: 9:00 am to 2:00 pmSunday: Closed, messages answered Monday
- Workshop
- 2140 Cattlemen Road, Suite 4, Sarasota, FL 34232
We do bathrooms only. If you need a kitchen, an addition or whole-home work we will give you two names of people who do it properly.