How to Make Shower Pans Over Cement Floors

Cut four 2-by-3- or 2-by-4-inch boards down to the lengths that you want to make the sides of the shower pan to create a frame. If you would like a 24-by-36-inch shower pan, for instance, cut two boards to 24 inches and two boards to 40 inches and then place the 24-inch boards inside the ends of the 40-inch boards so that the space inside the boards measures 24-by-36 inches. Drive two nails through each end of the 40-inch boards and into the 24-inch boards to secure the frame together.

Set the wood frame over the cement floor where you want to build the shower pan so that a floor drain sits inside the shower pan area. Place two bricks against the outside edge of each side of the wood frame to keep the frame from moving as you build the shower pan. If the floor drain has a drain cover, remove the screws from the drain cover and take the cover up from the floor.

Apply pre-mixed concrete to the surface of the cement floor inside the wood shower pan frame. Use a flat trowel to spread the mix to a depth of approximately 1 inch over the entire shower pan area. Then, start sloping the concrete upward, leaving the 1-inch depth around the drain and creating a steady slope to an approximately 2-inch depth at the wood frame.

Build a concrete ledge around the perimeter of the shower pan up to the height of the wood frame walls. Make the ledge 2 to 3 inches thick all the way around the shower pan. Once the concrete begins to firm, slide a 4-inch putty knife along the inside walls of the frame to loosen the concrete from the wood. Allow the concrete to set up for 48 hours before completely removing the wood frame from the floor.