Dear James: My balance is worse than when I was younger so I want to build a seat for my shower stall. What are some basic construction and sizing tips for making one myself? — John A.

Dear John: A shower seat is a wonderful convenience feature for any age group. While you are building and installing the shower seat, you should also install some grab bars. Make sure to install them according to the manufacturer’s instructions because they have to support a lot of weight when needed.

A shower seat can be made to any size that is comfortable to sit on. It would be wise to make it a height so your feet can rest on the bottom of the stall when seated. This makes it easier to stand up and also more convenient when she shaves her legs.

First, sit on a chair and measure your position to get a feel for how deep to make the shower seat. An additional four in inches depth is usually adequate if you want to also use it as a storage shelf for shampoo, soap, shaving items, etc. If you are going to build a shower seat for any member of the entire family to use, a seat height of about 15 inches is a comfortable compromise.

Building a shower seat that matches the shower stall walls always looks nice, but it may be much extra work.

Other materials, such as cultured marble or laminate, are easy to work with and water resistant. A dark shower seat that contrasts with the old tile will also look nice.

Most of these seat finishing materials will require a supporting frame beneath them to handle the weight of a person. Standard 2x4 lumber assembled with nails is adequately strong. With all the moisture present, it might be wise to build the frame with pressure-treated lumber and galvanized or stainless steel nails.

When finishing the shower seat with tile, make the frame about one inch smaller than the seat’s finished size to allow room for the plywood or cement backer boards and waterproof membrane. When using other thicker finishing materials size the frame smaller accordingly.

Water leakage into the seat framing is always a potential problem. To minimize the possibility of leakage, cover the seat frame with a waterproof vinyl membrane. To do it properly, remove a few rows of floor tiles and extend the membrane under them.

Also make sure the seat slopes down away from the wall to keep water from standing on it. Only a slight slope is required or it may feel strange to sit on.

With the membrane in place, cover the frame with water-resistant cement backer board. It is especially important to use this material if you are going to finish the seat with tile. Be careful not to tear the membrane during this step. When you have completed installing the finishing materials, seal any gaps with standard clear silicone tub caulk.
