Floor Mud Calculator

Calculate how much floor mud or deck mud you need for a shower pan or floor base.

Use decimals when needed. This estimate updates live and is safe to tweak before you buy materials.

Estimated mud

Floor Mud Buying Guide

This guide helps you turn your floor mud calculator result into a cleaner purchase plan. Use it when you want fewer return trips, better waste assumptions, and a more realistic cart.

Step 1: Calculate the slope

A shower pan must slope 1/4 inch per foot toward the drain. The mud bed will be thin near the drain and much thicker at the walls. Calculate volume using the average depth.

Step 2: Buy specific 'Dry Pack' or 'Sand/Topping' mix

You cannot use standard concrete mix with gravel for a shower pan. You need a mix of sand and Portland cement (often sold as Sand/Topping mix or Deck Mud).

Step 3: Keep it dry

When mixing, add very little water. The consistency should feel like wet beach sand that holds its shape when squeezed. It should not pour like liquid.

Recommended for this job

Commonly paired tools and accessories

These are the practical extras people often forget until the last minute, especially when turning a rough estimate into a real purchase list.

Deck Mud Basevia Amazon.comWhy this helps: Common add-on that reduces last-minute store runs once the estimate is final.

Mortar Mixing Tubvia Amazon.comWhy this helps: Common add-on that reduces last-minute store runs once the estimate is final.

Disclosure: these may be affiliate links.

Floor mud cost planning rule of thumb

The sand/topping mix is cheap. The real costs are the PVC shower pan liner, metal lath, curb forms, and the liquid waterproofing membrane applied on top.