Can I Build My Shower Pan on a Raised Platform?

Weight of the Mud

• The dry pack mud used to build shower pans can weigh hundreds of pounds for larger shower pans as it is made up of sand, cement and water. As such, the raised platform must be able to support the weight. There are specific requirements for subfloors and joist placement for tile floors in order to ensure there is sufficient strength beneath the tile installation. This is especially true of raised platforms, as they aren’t part of the actual subfloor and must stand alone under the weight of the shower pan and tile.

Subfloor Requirements

• Ceramic tile installations require a minimum of two layers of 5/8-inch plywood to set on top of the floor joists. Natural stone installations on the other hand require even more. A minimum of two sheets of 3/4-inch material is required. Take this height into consideration when building your raised platform, as it must be strong enough to comply with the minimum requirements for tile floors so the installer can warranty the work according to manufacturer's guidelines.

Extra Floor Joists

• The floor joists for the platform must conform to the minimum requirements for tile installations just as much as normal tile floor tiles. The minimum placing is 16 inch on center for the platform joists. Place them on top of the joists for the actual floor or cross them in a perpendicular fashion so there is sufficient support for the weight of the mud plus the tile on the pan.

Extra Plumbing

• Bear in mind that if you are adding a raised platform to an existing home that is already framed, you will need to include extra plumbing for the height of the platform. If you are building the home and can add the plumbing while the rest of the plumbing is installed, this is the best method. Otherwise, ensure the drain is installed along with the platform itself so it can be adjusted during the mudding-in pahse of the shower pan according to the height of the finish tile material.