## Calculation formula in brief
1. Wall area = width × height.
2. Opening area = (width × height of door, if any) + (width ×
window height, if any).
3. Net masonry area = wall area − opening area.
4. Face of one brick (with joint) = (width of brick + joint) × (height of
brick + joint).
5. Bricks needed (net) = rounded up (net area / brick face).
6. Total reserve = user-entered reserve + 5% additional surcharge,
if the wall has a door and/or window (due to cut bricks on the edges).
7. Bricks to order = rounded up (net bricks × (1 + reserve / 100)).
8. Pallets/packages = rounded up (bricks to order / bricks in
pallet/package), if specified.
9. Price = bricks per order × brick price, if set.
Rows/columns (brick courses) are calculated separately using the grid method
(width/height of the wall divided by the brick pitch with the joint) and
are for information only — the basic calculation of the number is by area,
to remain correct in the presence of holes of arbitrary shape/position.