An inaccurate material estimate either leads to overspending or stops work when supplies run out. An accurate calculation saves both time and budget.
Calculating block quantity
First calculate the wall area (length × height), subtract openings (doors, windows), then divide by the area of one block. For example, when using a 29×19×39 cm block, always add a 5-10% margin for damage and cutting.

Calculating mortar
The amount of mortar depends on joint thickness — thinner joints need less mortar but require more precise block geometry.
The main rule
Always order 5-10% more material than the strict calculation requires — this covers transport damage, cutting waste, and unforeseen needs.

