What stone veneer is
Manufactured stone veneer is a thin, lightweight concrete product cast to look like natural stone. It is sold in boxes of flats, which cover the main wall area, and corners, L-shaped pieces that wrap outside corners and are sold by the linear foot. Natural thin stone veneer is sold the same way.
The calculation
- Net wall area = length × height − openings (doors, windows).
- Corner coverage: each linear foot of corner pieces also covers about 0.75 sq ft of wall, so subtract that from the flats area.
- Flats area = net area − corner coverage, plus a waste allowance (10% is typical, 15% for complex walls).
- Boxes of flats = flats area ÷ box coverage, rounded up.
- Boxes of corners = corner length × 1.05 ÷ linear feet per box.
- Mortar bags = net area ÷ coverage per bag.
Example
A 20 × 8 ft wall with a 3 × 7 ft door (21 sq ft) has 139 sq ft to cover. Two outside corners 8 ft tall give 16 linear feet of corners, which cover 12 sq ft. Flats: (139 − 12) × 1.10 = 139.7 sq ft, or 14 boxes of 10 sq ft. Corners: 16 × 1.05 ÷ 8 = 3 boxes. With one 80 lb bag of mortar for about 25 sq ft, you need 6 bags.
| Item | Typical coverage |
|---|---|
| Box of flats | 8 to 12 sq ft |
| Box of corners | 6 to 9 linear ft |
| 80 lb bag of type S mortar (setting bed) | 20 to 30 sq ft |
Check the coverage printed on the brand you buy: stone profiles and box sizes vary.
Installation basics
- Over wood framing, the wall needs a water-resistive barrier, metal lath and a scratch coat before the stone.
- Over clean, unpainted concrete or masonry, stone can be set directly.
- Leave a gap above grade (often 4 in) and above paved surfaces (often 2 in), and install a weep screed at the bottom.
Mortar for the scratch coat and grout joints comes on top of the setting bed; plan a few extra bags if you grout the joints.