Drainage, a French Lesson
Good fences make good neighbors, and so does good drainage. To make sure you aren’t going to adversely impact anyone else’s land, direct the water away from your house (and your neighbor’s house), toward an area with plants that could use some extra irrigation.
If you have a large garden area with sandy, naturally draining soil, connect the tub drain to your garden with ABS pipe, available at any hardware store. But if the space for your drainage field is more limited, you may want to install a French drain.
To do so, dig a trough 12 inches deep by 12 inches wide, making sure that it is at a lower elevation than your tub to allow gravity to do its thing. Six feet is a good length to shoot for, noting that you can shorten the pipe if your soil naturally drains quickly, or lengthen it if your soil drains slowly. The bottom of the trough should slope in the direction of the water’s flow. Fill the trough three-quarters of the way with gravel (½-inch to 1-inch gravel is appropriate here).
Prepare a 2-inch-diameter ABS pipe (length determined by your trough) by drilling ¼-inch holes along the length of the pipe, which will allow the water to drain. Place the pipe in the trough and cover it with more gravel to finish. This will go a long way toward helping your yard accommodate the bathwater.
Place Your Tub
Once you have a solid, level, drainable platform, a clawfoot tub can be installed by simply setting it in place (with the help of a few friends). But a fiberglass or acrylic drop-in tub insert will need a frame for support.
Each frame will be unique to the tub you choose, but the goal is to build four framing walls that, when attached at the corners, will support the rim of the tub ½ inch above your brick foundation (this ½ inch is for a layer of mortar, which will be explained shortly). Use pressure-treated two-by-fours to build the “walls” of this frame; it’s recommended, though not essential, to use a double header (two planks placed atop one another along the top of the frame), which will be supported by two-by-four studs cut to height and nailed (using galvanized framing nails) every 16 inches on center (see diagram on previous page for frame assembly example).
Once the individual walls are built, nail them together at the corners and do a dry run with your tub to see if it will fit into the frame before continuing. You want to make sure that the rim of the tub fits nicely over the top of the frame, this way it will be supported.