A stand-alone soaker makes a strong design statement. But once filled with water—not to mention a bather—it can easily weigh up to 500 pounds, straining the floor beneath it. Sistering the joists or doubling up a subfloor of 3⁄4-inch plywood under a pedestal or one-piece tub will shore up the floor. Cast-iron claw-foot? TOH ’s Tom Silva likes to play it safe with 2x material laid flat between joists and supported by cleats under the legs.
Keep in mind that you’ll be sacrificing deck space—a small table or stool can sidle up alongside for toiletries—and the lack of a ledge to rest on may not suit those with limited mobility. Factor in plumbing placement, too. A floor-mount tub filler offers floor-plan flexibility, but a wall- or deck-mount may make sense if plumbing’s already in the wall (and can save you big bucks on the faucet). Running supply lines in a built-out ledge, as shown above, will create some landing space. And if your water heater isn’t able to handle any increased demand, you may have to upgrade it. After all, what’s the point of a statement soaker if you’re going to be left out in the cold?
Remember to order enough flooring to cover the space under the cabinet, and install blocking behind the walls to support the extra weight. Tom also likes to add 6-by-6-inch steel L-brackets, especially when there’s a stone vanity top. Plumbing that comes out of the floor needs to be roughed into the wall first, unless it’s an exterior wall in a cold climate. Then, to guard against frozen pipes, keep them tight to the wall and box out a surround painted to match.
Whether you put in a center drain or a linear one off to the side, getting the floor pitch right is the key to keeping water from puddling or seeping out under the door. Using a tile-ready preformed shower pan can take away the guesswork. You need a 1⁄4- to ½-inch pitch over 4 feet or less, says Tom—and you may need to build up the whole bathroom floor first to allow for the slope. Also, be sure the drain sits lower than the tile during installation.
TIP: SAFETY FIRST
Even if it drains properly, a wet shower floor is slippery. Boost traction with matte, honed, or textured tile in a small size with plenty of grout lines. And take this opportunity to install at least one grab bar.
Thanks to Tom Silva, Silva Brothers Construction