Floor Mud for a 3 by 5 Shower Pan: 3 Bags at 1 Inch, 4 Bags at 1.5
You stand in the masonry supplies aisle at the yard with a shower pan to build. Pallets of bagged mortar sit in front of you, and one of those bags does a job none of the others do. Floor mud is the mortar bed that goes under tile. It is the layer a tile setter floats and slopes before a single tile goes down.
Rockhouse stocks Sakrete Floor Mud Mix (50 lb.) at $18.00 per bag. This guide says what floor mud is, what it is not, what one bag covers, and how to count bags for a real shower pan. The tile setter mixes and floats it. Rockhouse sells the bag.
Rockhouse runs a 7-acre stone yard in Hot Springs Village with Bennett Brothers of Hot Springs heritage since 1972. The yard stocks the mortar, weighs the pallets, and loads your trailer with a forklift. Your own crew does the setting.
What floor mud does under a tile floor
A tile floor needs a flat, stable base with the right slope, and floor mud is the mix that makes it. The Sakrete Floor Mud Mix (50 lb.) is a Portland cement and sand blend packaged as a mortar bed mix. It floats into a smooth substrate that takes a precise slope and gives ceramic or natural stone tile a crack-resistant base.
The manufacturer lists the places it goes: shower pan bases, sloped surfaces, traditional mortar beds, over concrete floors, roof decks, concrete decking and stairs. It works in dry or wet applications. The bed can take tile immediately after floating. The setter finishes the tile within 24 hours, or the bed waits 28 days for a full cure before tile goes on.
What floor mud is not
Buyers mix up two products with floor mud at the counter, and both do a different job.
Floor mud is not the adhesive that holds the tile down. A tile adhesive is a separate product that goes on top of the cured bed. Floor mud makes the bed itself.
Floor mud is not a wall mortar either. Laying block or stone takes a masonry cement. For that work Rockhouse stocks Pro Mix Type S Masonry Cement - White (80 lb.) at $19.95 per bag, and the yard's post on Type S mortar coverage explains the four masonry grades. Bring the floor mud home for the pan and the Type S for the wall.
What one 50 pound bag of floor mud covers
The manufacturer gives one coverage figure: a 50 pound bag yields 6 square feet at 1 inch deep. The application depth runs from 1/2 inch up to 2 inches. Coverage moves with depth in a straight line, so the same bag covers 12 square feet at 1/2 inch, 4 square feet at 1.5 inches, and 3 square feet at 2 inches.
A sloped pan is thicker at the walls than at the drain. The bag count therefore comes from the average depth across the pan, and the average depth is a number you measure from your own layout. Bags come whole. Every count rounds up.
Count bags for a 3 by 5 foot shower pan
A 3 foot by 5 foot pan is 15 square feet. At a 1 inch average depth that pan needs 2.5 bags. Round up to 3 bags at $54.00. At a 1.5 inch average depth it needs 3.75 bags. Round up to 4 bags at $72.00.
A wider pan scales the same way. A 4 foot by 6 foot pan is 24 square feet, and at 1 inch average depth it needs 4 bags at $72.00. At 1.5 inches it needs 6 bags at $108.00. The yard checks the count for free when you call with the pan dimensions and the average depth.
How the slope sets the average depth
The average depth is the number most first-time buyers get wrong. Measure it. A shower pan slopes toward the drain, so the bed is at its thickest along the walls and at its thinnest at the drain ring. Measure the planned depth at the wall and the planned depth at the drain, add them, and divide by two. That is the average depth for the bag count.
Put numbers on it. A pan that runs 1.5 inches at the walls and 0.75 inch at the drain averages about 1.1 inches. On a 15 square foot pan the count at 1 inch is 2.5 bags. Multiply by 1.1 and the count at the real depth is 2.75 bags. Round up to 3 bags at $54.00. A pan that runs 2 inches at the walls and 1 inch at the drain averages 1.5 inches, and the 15 square foot pan takes 4 bags at $72.00.
An entryway floor or a mortar bed over a slab has no slope. The depth is the same everywhere. Measure it once and divide 6 square feet by that depth in inches to get the coverage per bag. A flat bed at 3/4 inch gets 8 square feet from every bag.
The water ratio is on the bag
The most common question about this product is the water ratio, and the manufacturer's product page does not state it. The bag carries the water line. Read it there. Measure the water for every batch with the same container. A batch mixed wet floats easily and cures weak, and a batch mixed dry will not slope. Never guess the water.
Buy the bags for the whole pan at once
A mortar bed floats in one session. A setter who runs out of mix halfway across the pan cannot stop and come back, because the first half starts to set while the second half waits on a trip to the yard. Buy the full count before the mix starts, and buy the rounded-up number. One unopened bag left at the end costs $18.00. A trip to the yard mid-float costs the afternoon.
The 24 hour window works the same way. The manufacturer's line says the bed takes tile immediately after floating and the tile goes on within 24 hours. Past that window the bed cures for 28 days before tile. So the tile, the adhesive and the setter need to be on site the same day the bed goes down. Plan the bags and the tile as one delivery.
Floor mud on a floor, a deck or a stair
The shower pan is the common job, and the same bag does four others the manufacturer lists. Over a concrete floor it floats a flat bed that takes out dips before tile goes down. On a roof deck or a concrete deck it builds the slope that carries water to a drain. On stairs it levels a tread before a stone or tile tread goes on. In each case the coverage rule holds: 6 square feet per bag at 1 inch, and the depth you float sets the count.
A sloped deck is the one to measure with care. A deck that falls from 2 inches at the wall to 1/2 inch at the drain across 60 square feet averages 1.25 inches, and at 6 square feet per bag per inch that is 60 divided by 6, times 1.25, which comes to 12.5 bags. Round up to 13 bags at $234.00. A deck that size is a pallet-scale order, and the yard delivers it.
Why the bed matters more than the tile
A tile floor fails from underneath. A bed that dips holds water, a bed that slopes the wrong way sends water to the wall, and a bed that cracks takes the tile with it. The floor mud is the part nobody sees once the job is done and the part that decides whether the floor lasts. That is why a setter measures the depth, counts the bags, and mixes to the water line on the bag. The $18.00 bag is the least expensive material in the shower and the one that carries everything else.
Pick up the bags or have the yard deliver
Rockhouse stocks, sorts, weighs, prices, loads and delivers. It never installs, sets or lays anything, and your own crew or your tile setter does that work. Orders load by the pallet, the super sack or the full truckload. At the yard the crew loads your trailer with a forklift.
Delivery is free on 3 or more pallets to Hot Springs Village and all of Garland County. Below three pallets the yard quotes the run. The yard coordinates freight to other regions, and contractors get delivery straight to the jobsite. The yard will meet or beat any stone supplier's price.
Contractors who buy every week open a verified pro account for trade pricing and net terms. Qualified buyers can open trade credit, and the Rockhouse Rewards Program gives tiered discounts to repeat and volume buyers. The online store shows inventory and pricing. The yard takes the order on the phone.
Call 501-532-1905 with the pan dimensions
A floor mud order takes one call once these numbers are in hand.
- The length and width of the pan, in feet.
- The average depth of the bed, in inches.
- The bag count you worked out after rounding up.
- Whether you collect at the yard or want it delivered.
Call 501-532-1905 and the yard will confirm the bag count and set the bags aside. Or come to 5643 N Hwy 7, Hot Springs Village, Monday through Friday from 7:30 AM to 4:30 PM, and load them straight from the aisle.