How to Build a DIY Shower Pan

How To Build a DIY Shower Pan

1. Block Between the Studs

   Cut two-by-six lumber to fit between the studs of the shower stall. Where you have obstructions such as pipes, use one-by-six lumber or use a router to create a groove to accommodate the obstruction. Blocking allows you to run the waterproofing material up the sides of the shower, which creates the DIY shower pan liner.

2. Cover the Drain

   Use tape and plastic to cover up the shower drain so that the mortar and other debris will not clog it.

3. Add the Tar Paper

   Cut and lay down the tar paper on the floor of the shower. Fasten it down with roofing nails or staples.

4. Mix the Mortar

   In the mixing tray, mix the mortar with water, using a garden hoe. Use only a little bit of water at a time to maintain a stiff, peanut butter-like consistency.

5. Spread the Mortar to the Borders

   Wearing waterproof gloves, dump the mixed mortar onto the shower floor. First by hand, then with the trowel, spread the mortar around the base, mounding it higher around the edges. Aim for a height of about 1-1/2 inches on the border.

6. Taper Down the Mortar

   With the flat trowel, taper down the mortar towards the shower drain. Use the scrap piece of two-by-four and level to continually check the tapered slope. You can also use the two-by-four as a screed to smooth down the mortar. Let this mortar bed dry for at least 24 hours.

7. Add Silicone to the Drain

   Remove the top section of the shower drain by unscrewing or unbolting it. Run a thin bead of silicone around the perimeter of the drain.

8. Add the Shower Waterproofing Material

   Lay the waterproofing material on the floor of the shower, running it about five inches up each of the walls. Press the material firmly into the silicone on the shower drain. Fold the corners into place; do not cut the corner material. Nail the top of the waterproof material to the studs to prevent it from falling.

9. Replace the Shower Drain Top Cap

   With the utility knife, create slits for the four bolts on the shower drain to protrude upward. Replace the top cap and screw or bolt it tightly into position. Cut out the hole for the shower drain.

10. Add the Lower Section of Cement Boards

    You can now add the rest of the cement boards down to the level of the mortar bed.

11. Add a Reference Line to the Walls

    With the rest of the shower drain temporarily in place, draw a pencil or chalk line around the perimeter of the walls to add a reference line, which represents the top of the tile. Use the scrap two-by-four to help estimate the slope from the walls down to the shower drain.

12. Add the Top Mortar Layer

    Similar to the lower mortar layer that you created earlier, mix the mortar in the mixing tray, then dump it onto the floor of the shower. Build a high border around the perimeter of the shower, about 1/4-inch below the tile top perimeter line. With the trowel, taper down the mortar to the shower drain.

    Tip

    This top mortar layer must be very smooth, so take your time with it.

13. Install the Tile

    Spread out thinset with the notched trowel and press the tile into the thinset. Use tile spacers to maintain proper distance between tiles. Let the tile fully cure. Spread grout across the surface of the tile with the rubber tile float.