Stone veneer calculator: how many boxes of stone veneer do I need?
19 boxes of flats + 4 of corners
185.9 sq ft of flats, 17.6 ft of corners, 10% extra · 21 bags of 80 lb mortar, scratch coat and setting bed · for a 24 × 8 ft wall
Run your own numbers
Enter it the way you measured it: 4.5, 4 1/2,
3/8 or 10' 6".
19 boxes of flats + 4 of corners
185.9 sq ft of flats, 17.6 ft of corners, 10% extra · 21 bags of 80 lb mortar, scratch coat and setting bed
Source: Ply Gem Stone installation guide and spec guide, Coronado's estimating sheet, the MVMA installation guide and the QUIKRETE Veneer Stone Mortar data sheet, read October 26, 2026. Data sheet (PDF)
A 24 × 8 ft wall with a 15 sq ft window and 16 ft of outside corners takes 19 boxes of flats and 4 of corners by Ply Gem's method, 10% extra included, plus 21 bags of 80 lb mortar.
A worked example
A wainscot 17 1/2 ft long and 3 1/4 ft high with 6 1/2 ft of corners, Coronado's method at 5% extra and 60 lb mortar bags needs 54.6 sq ft of flats and 6.5 linear ft of corners. 56.88 sq ft of wall less 6.5 × 3/4 = 4.88 sq ft taken by the corners is 52 sq ft, and 5% more is 54.6. The mortar, two 1/2 in layers over 56.88 sq ft at 13 sq ft per 60 lb bag, is 9 bags.
How do you count corners in a stone veneer estimate?
By their length in linear feet, and each foot of corner covers some wall, so the flats go down: half a square foot per linear foot by Ply Gem's guide, about 3/4 by Coronado's. On 16 ft of corners that is 8 or 12 sq ft fewer flats.
How many bags of mortar for stone veneer?
An 80 lb bag of QUIKRETE Veneer Stone Mortar covers about 17 sq ft at 1/2 in, one scratch coat. The MVMA guide adds a 1/2 in setting bed on the back of each stone, so the two layers take about 8.5 sq ft per 80 lb bag, or 6.5 per 60 lb bag.
What else it is called
Also searched as a stone veneer calculator in square feet, manufactured stone calculator, stone veneer corner calculator or stone veneer mortar calculator. Flats are the wall pieces; corners are L-shaped pieces sold by the linear foot.
Boxes and mortar by wall size
| Wall, length × height | Outside corners | Ply Gem boxes, flats + corners | Coronado flats, sq ft | 80 lb mortar bags |
|---|---|---|---|---|
| 10 × 3 ft | 6 ft | 3 + 2 | 28.1 | 4 |
| 16 × 4 ft | 8 ft | 7 + 2 | 63.8 | 8 |
| 20 × 8 ft | 16 ft | 17 + 4 | 162.8 | 19 |
| 24 × 8 ft | 16 ft | 21 + 4 | 198 | 23 |
| 30 × 9 ft | 18 ft | 29 + 4 | 282.2 | 32 |
| 40 × 9 ft | 18 ft | 39 + 4 | 381.2 | 43 |
Two outside corners the height of the wall, no openings, 10% extra. Ply Gem: half a square foot of flats less per linear foot of corner, 10 sq ft of flats and 5 linear ft of corners per box. Coronado: 3/4 sq ft per linear foot. Mortar for a 1/2 in scratch coat and a 1/2 in setting bed, 17 sq ft per 80 lb bag of QUIKRETE Veneer Stone Mortar for each.
Where the numbers come from
- Ply Gem Stone Installation Guide, estimating steps 1 to 4: flats = width × height less openings, and «take half the number» of corner linear feet off; order 10% more square feet and linear feet; with a standard 1/2 inch grout joint, «flat stones are 10 square feet per box», 8.5 if dry stacked, and «All corner stones are 5 linear feet per box». Read October 26, 2026. Ply Gem Stone installation guide (PDF)
- Coronado Stone Products, Estimating Stone Veneer Quantities: «one linear foot of stone veneer corners consumes approximately 3/4 square foot of wall coverage», and 5 to 10 percent extra flats for cutting. Coronado estimating sheet (PDF)
- Mortar layers: Masonry Veneer Manufacturers Association, Installation Guide for Adhered Manufactured Stone Veneer, 5th edition (2018): a nominal 1/2 in scratch coat, the back of each stone buttered 1/2 in, and scratch coat plus setting bed «nominally 1 in.» MVMA installation guide (PDF)
- Mortar bags: QUIKRETE Veneer Stone Mortar (No. 1137) data sheet: an 80 lb bag yields about 0.71 cu ft and covers about 17 sq ft as a scratch coat at 1/2 in; a 60 lb bag 0.53 cu ft and 13 sq ft. QUIKRETE 1137 data sheet (PDF)
- The rest is arithmetic: boxes = square feet or linear feet with the extra ÷ the box, rounded up; mortar bags = wall less openings × 2 layers ÷ the bag's coverage at 1/2 in.
The mortar count is the scratch coat and the setting bed; grouting the joints between stones takes more, and none of the four documents gives a figure for it. Dry-stacked Ply Gem flats cover 8.5 sq ft per box instead of 10.
By Javier Miralles · Last updated . How this site is made.
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