How to Build Shower Pans

Learn the professional way to build custom shower pans

Time

Multiple Days

Complication

Intermediate

Cost

$101–250

Introduction

Learn how to build a custom-sized, waterproof shower pan for a curved shower enclosure by following these clear, detailed photos and step-by-step instructions.

Tools Required

Materials Required

  • 1-1/4-in. roofing nails
  • 1"x3/4"
  • 10d galvanized nails
  • 1x4
  • 2x4
  • 2x6
  • three-in. drywall screws
  • Ceramic floor mix
  • Duct tape
  • Fiberglass mesh tape
  • Galvanized expanded metallic lath
  • Hardboard siding
  • Shower drain assembly
  • String
  • Sparse-prepare mortar
  • Tile capitalist board
  • Vinyl membrane

These days, if you want to put in a shower, you tin simply become to a abode middle and option upwardly a fiberglass unit. Before that was possible, pros had to build a custom shower pan past mixing and applying mortar, troweling it flat, and laying ceramic shower floor tile.

Although fiberglass units make shower pans quick and easy, they lack the elegance of a handcrafted mortar and tile flooring. So if you'd like to install a tile shower and are willing to build your ain custom shower pan, y'all'll exist able to tile information technology to match the walls. And with a mortar and tile flooring, your shower tin can be whatsoever shape. (For example, see How to Install a Glass Block Shower.) In fact, no matter what its shape, if the shower you have in listen doesn't conform to the rigid size requirements of a manufactured base of operations, a mortar floor may exist your only alternative.

You'll find that the price of the materials used in a hand-crafted base is roughly the same as the cost of a comparably sized fiberglass pan. The downside is that instead of just plugging a manufactured unit into the opening, you'll have to do a lot more piece of work. You'll demand a couple of days to form and tamp in ii layers of mortar, deal with some tricky vinyl membrane liner and then install the tile. Installing shower pans isn't a project for winging information technology or taking shortcuts. Poorly installed shower pans will leak, and the only correct way to fix a poor installation is to rip out not only the base of operations simply besides the shower walls.

The shower pan installed in this projection is somewhat complicated, but the key techniques are the same for even the simplest shower — one the size of a phone booth. If you have feel with cement and some bones trowel skills, y'all should exist able to practice nearly any size shower floor in less than two days, excluding tile work.

Beefcake of a Mortar Shower Floor

The get-go layer, chosen a sloped fill, is simply a mortar subfloor. It's sloped toward a special two-piece clamping-type bleed (bachelor at any home center) that is made specifically for a mortar bed shower floor. The sloped fill slants from the drain toward the perimeter of the shower with a slope of one/four inch per human foot. Since our shower had an average width of three anxiety, we sloped up from the 1/four-inch thickness of the drain to a ane-inch thickness around the shower walls and curb to get the necessary 3/iv-inch slope.

The second layer, chosen the pan, is a durable CPE (chlorinated polyethylene) membrane. This vinyl liner is turned up at the edges to create a waterproof membrane in the shape of a shallow pan. Water that works its way through the grout and the top layer of mortar will flow down the slope to be drained through the weep holes of the drain. On top of the pan is a layer of expanded galvanized metal lath to reinforce the mortar. Over the lath, a sloped mortar bed is laid using the same 1/4-inch-to-the-foot slope rule nosotros used for the sloped fill up.

Shower curbs help by containing water in areas that aren't bordered by walls. If a bleed becomes blocked, peradventure past a washcloth over the surface, a curb buys you time. It will dam the h2o within the shower for a while before information technology lets it run over onto the bathroom floor.

(For a larger version of this drawing, see Additional Information, below.)

This illustration shows the basics of how to build a shower pan.

Project step-by-footstep (14)

Stride 1

Draw the Flooring

  • Describe the outline of the shower floor on the subfloor to employ as a pattern for setting the mortar forms.
  • Nail an 8d nail next to the wall and strike a 65-inch arc for the curved form lath.

Step 2

Ostend the Layout

  • Lay out the shower on the subfloor using your finish materials—in this case, tile and glass block—to help define its size and shape for shower pan installation.

Caution!

The shower we designed and installed here weighs upward of one,000 lbs., or about the same as a spa with a couple of people in information technology! If you alive in an older home with 2x6 or 2x8 flooring joists, you may need to beef up the floor with some beams or extra floor joists. If you lot're unsure, consult a building inspector. And if you have a house that was built in the '70s, it could have a 5/8-inch particleboard underlayment that will demand to exist removed before starting.

Step iii

Open the Walls

  • Cut the drywall so that the seam of the drywall and cement board falls halfway behind the glass block.
  • Install backers in the stud wall to support the cement board/drywall seam.
  • Cut the summit of the drywall at 6 feet, 2 inches above the plywood floor to allow for the slope fill and two layers of three-feet wide cement board.

Step 4

Class the Bend

  • Toe-blast 2x6 blocking at the base of the shower on interior walls to support the vinyl liner.
  • Toe-screw 2x4 blocks to the subfloor every 12 inches and 1/ii inch away from the line to let for the thickness of the hardboard siding.
  • Rip the siding to 3-i/two inches and screw it to the behind of the blocks for curved curbs.
  • Toe-spiral 2x4s for directly curbs and cut off the excess hardboard after forming.
    • Pro tip: Toe screws are easier to remove later the mortar work is done.
  • Smash in permanent 1-inch thick screed boards against walls.
  • Rough-in the copper plumbing and drain h2o lines.

Planning Shower Layout

Proceed these elements in mind when you're sizing and positioning your shower:

The tile layout. Information technology'southward easier to make up one's mind the size of the shower if your wall tile is selected ahead of time. Since we had 12-inch tile, we fabricated pocket-size alterations in the size until nosotros had wall lengths that made full tiles come out just behind the inside edge of the glass block.

Shower doors. If your shower will have a door, pick it out in accelerate to make certain the shower opening will adjust it. Don't forget to allow for the thickness of the tile and the cement lath. When you're determining the size of the shower door and the management information technology should swing, consider other bathroom doors and fixtures.

Plumbing. It'due south plainly much easier to hook upwards a new shower that is located near existing plumbing. Copper water lines, sewer drain lines and vents tin be hooked up to pipes at a neighboring bathroom. Our shower backed upwards to a mutual wall that contained all the plumbing nosotros needed. If you're installing your shower in a remote location, it can be tough to get to the sewer drain and still keep the shower drain inside the required altitude from the bleed h2o vent. You may need to rip out walls or the ceiling below the shower to attain claw-ups if the next level down is finished. Sometimes plumbing a new bath is more piece of work than building the shower from scratch.

Step five

First Layer of Mortar

  • Remove the top half of the shower bleed and plug the drainpipe with a rag to prevent droppings from falling into the plumbing.
  • Pack the mortar with a wood bladder, then screed the commencement layer of mortar.
  • Employ removable 1-inch screed blocks along curbs to establish a i-inch to 1/four-inch gradient toward the drain.
  • Work the surface smooth with a forest float and smooth with a steel trowel.
  • Allow the mortar harden overnight.

Footstep half dozen

Lay in the Liner

  • Tack up scrap pieces of vinyl liner to protect the actual liner from the sharp edges of plumbing or electrical plates.
  • Install the liner, running it up onto the walls at least six inches, and blast it to the studs with roofing nails at the top edge.
  • Feel the drain flange bolts with your fingers and draw and advisedly cutting the liner to fit simply exterior the bolts.
  • Cut off the liner against the curved edge i/ii inch below the height of the form.

Step 7

Fold the Corners

  • Chisel out the inside corners of the framing to create a recess for the liner folds.

Step eight

Brand a Drain Hole

  • Cutting out the vinyl liner for the drain with a utility knife, cutting just outside of the bolt holes.
  • Run a bead of silicone caulk around the outer edge of the flange.
  • Bolt down the top one-half of the drain assembly.
  • Cover the height of the drain with duct tape to protect it during the installation of the mortar bed and tiling.

Stride 9

Adhere the Tile Backer Lath

  • Install cement lath over the vinyl liner and spiral it to the studs with coated cement board screws every eight inches.
  • Cut slots in the cement lath to get over curbed areas against the walls.
  • Tape the seams with fiberglass record and sparse-set mortar or mastic.
    • Pro tip: When setting the cement board, face the smooth side out. This makes it much easier to spread the tile adhesive and get a apartment surface for tiling and for drawing tile layout lines.

Footstep ten

Add together the Metal Lath

  • With a pair of tin snips, cutting and lay in galvanized expanded metal lath on summit of the liner simply curt of the cement board edges.
  • Bend 12-inch x 3-pes lengths of board over a 2x4 for curb reinforcement pieces.
  • Keep the height barely under the grade heights.
    • Pro tip: For a curved curb, make a series of slits every x inches to assist information technology bend to the shape of the hardboard class.
    • Pro tip:Avoid walking on the lath. Its sharp edges can puncture your waterproof membrane.

Step 11

Form the Curb

  • Fold the vinyl liner and drop the pre-bent curb lath over the elevation of it.
  • Poke a galvanized 10d nail through the lath and top border of the liner to keep information technology from collapsing while yous pack the curb with mortar.

Step 12

Cover the Board with Mortar

  • Snap chalk lines against the cement lath, making them one-i/4 inch higher up the sloped make full.
  • Suit the top of the drain by screwing it upward or down until it is 1 inch to a higher place the tiptop of the slope fill.
  • Pile mortar against the wall and compact it down to the line.
  • Use the packed mortar as a guide for screeding off the mortar between the wall and the drain.
  • Employ the straightedge to locate high or low areas.
  • Pack in mortar to make full depressions, and scrape off excess in the high spots.
  • Employ a steel trowel to smooth the bed and to tool sharp edges at all corners for a cleaner tiling task.

Footstep 13

Mortar the Curb

  • Pack mortar into the lath with a wood float around the folded liner, and then screed with a 3/iv-inch plywood jig.
  • Afterwards screeding, tool the edges of the curb with a trowel to obtain well-baked edges.

Pace fourteen

Adapt the Drain

  • Heighten the shower drain by unscrewing it until information technology is the aforementioned height equally the floor tile.
    • Note: You accept to practise this before the mortar sets.

Additional Information

  • Since this article was get-go published, new materials take become available for projects like this. Meet Pro Tile Tips for more than data.
  • Anatomy of a Mortar Shower Floor

Originally Published: November 26, 2022