How it works
The calculator takes the wall area, subtracts doors and windows, then subtracts the wall area that corner pieces will cover. It adds the extra for cutting and divides by the box coverage you enter.
Wall area to cover = Length × Height − Σ (Width × Height × Count of openings)
Area covered by corners = Corner length × Corner width
Flats = (Wall area to cover − Area covered by corners) × (1 + Extra ÷ 100)
Corners = Corner length × (1 + Extra ÷ 100)
Boxes of flats = ⌈ Flats ÷ Coverage per box ⌉, Boxes of corners = ⌈ Corners ÷ Corners per box ⌉
⌈ ⌉ means rounding up to the next whole box. Coronado Stone’s own example works out like this: 800 sq ft of wall minus 120 sq ft of openings leaves 680 sq ft. Its 80 linear feet of corners at 3/4 sq ft per foot cover 60 sq ft, which leaves 620 sq ft. With 10 % extra, that is 682 sq ft of flats.
Flats and corners
Manufactured stone veneer is sold as flats, priced and packed by the square foot, and corners, packed by the linear foot. A corner piece is L-shaped. It has a long and a short return that wrap around the corner, so it covers some wall on both sides. If you order flats for the whole wall and corners as well, you pay twice for the strip along each corner. That is why the corner area comes off the flats.
The Coronado Stone estimation guide puts the average at about 3/4 sq ft of wall for each linear foot of corners. Smaller profiles typically consume less and larger profiles more. This calculator asks for that figure as a width: 3/4 sq ft per linear foot is a strip 9 in wide along the corner. In metric, the same figure is about 0.23 m² per meter, entered as 228.6 mm. If your manufacturer states a different number, convert it the same way (sq ft per linear foot × 12 = inches).
Measuring corners
Measure the height of every outside corner of the walls you are covering and add them up. Coronado’s guide also tells you to include the edges of doors and windows that will get corner pieces. A 4 × 5 ft window with corner pieces on both sides and the head adds 5 + 5 + 4 = 14 linear feet, for example. Enter 0 if the wall has no corners, such as a single flat accent wall that stops at trim.
Extra for cutting
Coronado Stone suggests ordering 5–10 % extra stone for loss from cutting and trimming. The default here is 10 %, the figure in its worked example. The same percentage is added to corners. A plain rectangular wall can be at the low end. A wall with many openings, outlets, steps or angles is better at the high end.
Coronado also notes that its grouted profiles are packaged assuming a ½ in grout joint. A narrower joint uses more stone and a wider one less, so check your product’s guide if you plan to change the joint.
Boxes
Box coverage varies a lot between products and box sizes, so the calculator does not assume one. Enter the square feet of flats per box and the linear feet of corners per box from the label, and the calculator rounds up to whole boxes. Without box sizes, you still get the flats and corners to order.
What is not included
The calculator counts stone only. Water-resistive barrier, lath, scratch coat, mortar for setting and grouting, and trim at the top and bottom of the wall come from the manufacturer’s installation guide. Wall preparation and moisture management are as important as the stone itself, so follow that guide and local code. Blend stone from several boxes as you go so the color and size stay even across the wall.
Worked example
Inputs
- Wall length
- 40 ft
- Wall height
- 20 ft
- Doors & windows (no stone) 1
- Width 5 ft, Height 6 ft, Count 4
- Corner length
- 80 ft
- Wall width covered by corners
- 9 in
- Flats coverage per box
- 10 sq ft
- Corners per box
- 6 ft
- Extra for cutting
- 10 %
Result
- Wall area to cover
- 680 sq ft
- Area covered by corners
- 60 sq ft
- Flats to order
- 682 sq ft
- Corners to order
- 88 ft
- Boxes of flats
- 69
- Boxes of corners
- 15
Common mistakes
- Ordering flats for the full wall and corners on top. The corner pieces cover part of the wall, so their area comes off the flats.
- Measuring only the outside corners of the house. Window and door returns that get corner pieces count too.
- Using one product’s corner factor for another. Larger profiles consume more wall area per foot of corner than smaller ones.
- Assuming every box covers the same area. Box coverage differs between brands, profiles and box sizes; read it from the label.
- Skipping the extra for cutting. Cuts around openings, outlets and the top course all create offcuts.
Assumptions and limits
- Walls are rectangles of length × height; doors and windows are rectangles of width × height × count. Gables can be entered as an equivalent rectangle (½ × base × height).
- Area covered by corners = corner length × the wall width the corners cover, 9 in (3/4 sq ft per linear foot) by default, following the Coronado Stone estimation guide.
- The extra-for-cutting percentage is added to both flats and corners. Boxes are rounded up to whole boxes.
- Lath, scratch coat, mortar and water-resistive barriers are not included.
- This is a material estimate only. Wall preparation, attachment and moisture management follow the manufacturer’s installation guide and local code.
Frequently asked questions
How do I calculate how much stone veneer I need?
Multiply the wall length by its height, subtract doors and windows, and subtract the area the corners cover. Coronado Stone’s guide works an example of 800 sq ft minus 120 sq ft of openings minus 60 sq ft for 80 linear feet of corners, which is 620 sq ft, plus 10 % extra for 682 sq ft of flats.
How much wall does one linear foot of corners cover?
Coronado Stone says that on average one linear foot of corners consumes about 3/4 sq ft of wall, with smaller profiles using less and larger ones more. Use your manufacturer’s figure if it publishes one.
How much extra stone veneer should I order?
Coronado Stone suggests ordering 5–10 % extra to cover loss from cutting and trimming. Walls with many openings or angles may need the higher figure.
How many square feet are in a box of stone veneer?
It depends on the product and the box size. Read the coverage from the box label or the product data, then enter it in the calculator to get the number of boxes.
Do I need corners for inside corners?
Coronado Stone’s estimation guide counts corners for outside corners and for doors and windows that will get corner pieces. For inside corners, follow your manufacturer’s installation guide.
Sources
- Standard Stone Installation Guide – Stone Veneer Estimation Guide (2020) — Coronado Stone Products. "On average, one linear foot of stone veneer corners consumes approximately 3/4 square foot of wall coverage"; "Coronado Stone also suggests ordering 5-10 percent extra stone"; example 800 − 120 − 60 = 620 sq ft × 1.10 = 682.
- NIST Handbook 44, Appendix C – General Tables of Units of Measurement — National Institute of Standards and Technology. Exact unit definitions: 1 in = 2.54 cm, 1 yd³ = 27 ft³, 1 US gal = 231 in³, 1 lb = 0.45359237 kg.
Method reviewed November 3, 2026