Tips on Floating a Shower Pan

Add the Slope

• A mortar bed for supporting the base of a shower needs a specific amount of slope to keep water flowing toward the drain. It is best to establish this slope while floating the shower pan. Calculate the height of mortar you need at both the low spot around the drain and the high point along the edges of the shower so that it drops by 1/4 inch per foot, recommends the "Ultimate Guide to Ceramic & Stone Tile" from Creative Homeowner. Lay the minimum height first and then build up to the maximum with the float.

Use the Right Tools

• The wooden paddle known as a mortar float tool should only be used for part of the shower bed floating process. Use a trowel to dump the mortar in the frame and the float to compress and smooth it around, recommends Fine Homebuilding's "Renovating a Bathroom." Although the float will get the bed relatively smooth, the trowel should be used again for a final smoothing pass so that the shower pan lies on the right slope.

Pack It In

• Applying the right amount of pressure as you smooth the mortar with the float ensures that any pockets of air or loose material become pressed out. This creates a strong shower pan that won't crack and damage the tiles above it. The wooden float is perfect for this job because it allows you to lean your weight on the mortar while smoothing it, according to North American Tile. Check the slope for evenness all the way around the shower pan after floating.

Alternatives to Hand Floating

• A number of companies produce an automatic leveling shower pan kit that contains float strips. These lightweight strips of plastic or metal are marked to show the amount of slope that is needed. Once installed in the shower pan, you just add mortar to the height of the float strip and smooth the mortar bed with the angle of the strip. This prevents the need for calculating and checking the slope manually.