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Deck Mud Coverage Chart

Use this deck mud coverage chart to estimate square feet per bag by bed thickness, then compare common shower pan and mortar bed sizes before you open the full calculator.

Download printable PDF Calculate exact bags

Coverage per bag by thickness

Coverage uses the same formula as the calculator: square feet per bag = bag yield divided by thickness in feet. A 60 lb bag is estimated at 0.45 cu ft, and an 80 lb bag is estimated at 0.60 cu ft.

Bed thickness 60 lb bag (~0.45 cu ft) 80 lb bag (~0.60 cu ft)
0.75 in 7.2 sq ft 9.6 sq ft
1 in 5.4 sq ft 7.2 sq ft
1.25 in 4.3 sq ft 5.8 sq ft
1.5 in 3.6 sq ft 4.8 sq ft
2 in 2.7 sq ft 3.6 sq ft
2.5 in 2.2 sq ft 2.9 sq ft
3 in 1.8 sq ft 2.4 sq ft

These are one-bag coverage estimates before waste. Sloped shower pans vary in thickness, so use average thickness for coverage planning.

Bags for common pan and bed sizes

This table assumes an average thickness of 1.5 in, 10% waste, and whole bags rounded up. Sloped shower pans often run around 1.25 in at the drain and thicker at the perimeter, so 1.5 in is a typical average planning thickness.

Pan or bed size Area Base volume 60 lb bags 80 lb bags
3 x 3 ft 9 sq ft 1.13 cu ft 3 bags 3 bags
3 x 4 ft 12 sq ft 1.50 cu ft 4 bags 3 bags
3 x 5 ft 15 sq ft 1.88 cu ft 5 bags 4 bags
4 x 4 ft 16 sq ft 2.00 cu ft 5 bags 4 bags
4 x 5 ft 20 sq ft 2.50 cu ft 7 bags 5 bags
4 x 6 ft 24 sq ft 3.00 cu ft 8 bags 6 bags
5 x 5 ft 25 sq ft 3.13 cu ft 8 bags 6 bags

Bag counts include 10% waste. Check the yield printed on your product because bagged floor mud and sand topping mixes can vary.

Which thickness row should I use?

Pick the row that best represents the average mud thickness you are estimating. A sloped shower pan is not one thickness everywhere, so a planning average is usually more useful than reading only the thinnest drain-side measurement.

Chart row Use it for Planning note
1 in Thin flat-bed planning where product instructions allow it Coverage is higher, but a thin bed leaves less margin for uneven substrates.
1.25 in Common drain-side planning check for shower pan estimates Use this as a minimum-thickness planning row, then account for slope toward the perimeter.
1.5 in Average-thickness shortcut for many small sloped pans The common-size table below uses this row with 10% waste.
2 in Thicker mortar beds, build-up areas, or conservative flat-bed checks Coverage drops quickly as thickness increases, so bag count rises.

Final thickness, slope, waterproofing sequence, and code details must come from product instructions and qualified installation guidance. This page only estimates material quantity.

Interactive estimate

Convert area, thickness, and bag size

Enter length and width, or enter direct square feet. The widget uses the deck mud calculator with a flat mortar bed, 10% waste, and the selected bag yield.

Enter dimensions to see a planning estimate.

This widget is a planning estimate. It does not replace product instructions, waterproofing details, local code, or qualified installation guidance.

How to use this chart

  1. Choose the bed thickness or use the average thickness from your sloped shower pan plan.
  2. Read the square feet covered per bag, or use the size table for common pan footprints.
  3. Add waste for packing loss, uneven substrate, and field trimming, then round up to whole bags.
  4. For sloped pans, custom bag yields, or a pre-slope layer, use the deck mud calculator.

Common shower pan planning checks

For a small 3 x 5 ft shower pan, the common-size table uses a 1.5 in average thickness and 10% waste, which gives about 5 bags at 60 lb or 4 bags at 80 lb. A 4 x 5 ft pan is closer to 7 bags at 60 lb or 5 bags at 80 lb under the same assumptions.

Use these rows as a first pass only. If your pan has an off-center drain, a long run to the farthest wall, a separate pre-slope, or a different bag yield, use the editable deck mud calculator.

FAQ

How much deck mud per square foot?

At 1.25 in thick, deck mud uses about 0.10 cu ft per sq ft. One 60 lb bag covers about 4.3 sq ft, and one 80 lb bag covers about 5.8 sq ft at that thickness.

What thickness should deck mud be?

For shower pans, plan around 1.25 in minimum at the drain, then slope about 1/4 in per ft to the perimeter. Flat floor mud beds commonly use about 1.5 to 2 in, but product instructions and qualified guidance should set the final thickness.

Is deck mud the same as floor mud?

Yes. Deck mud and floor mud usually mean the same dry-pack sand-and-portland mix, commonly discussed around 4:1 to 5:1 sand to cement by volume. The names are often used interchangeably.

How many pounds of mud for a shower pan?

A typical 3 x 5 ft shower pan can need about 4 bags of 60 lb mix, or roughly 240 lb, before extra waste. Use the calculator for your exact pan size, slope, thickness, and bag yield.