How much wastage should I add to the brick calculator’s raw quantity?

A modest wastage allowance is already built into the calculator's output to account for breakage during transport, handling and normal cutting at corners and openings. Real-world wastage can run higher on sites with difficult access or inexperienced labour, so treat the calculator's figure as a reasonable planning baseline rather than an absolute ceiling. Keeping bricks covered and stacked properly on site is one of the simplest ways to keep actual wastage close to the estimate.