Metric Unit Calculator
The formula, your substituted values, and the evaluated result are shown below.
Udemy is an AI-powered skills acceleration platform transforming how companies and individuals across the world build the capabilities needed to thrive in a rapidly evolving workplace.
View offerAffiliate link — we may earn a commission at no extra cost to you.Estimate mortar requirements from area and coverage.
This is a planning estimate. Confirm dimensions, allowances, material specifications, applicable codes, and supplier requirements before purchasing or construction.
Estimate mortar requirements from area and coverage.
The calculator divides the area of work by how much area one unit of mortar covers, then adds waste:
Units = area (m²) ÷ coverage per unit (m²) × (1 + waste % ÷ 100)
A "unit" is usually a bag of premixed mortar, so the answer is the number of bags. The result isn't rounded, so round up when you buy.
For a single-skin wall of Australian standard bricks (230 × 76 × 110 mm) with 10 mm joints, the mortar takes about 0.017 m³ per square metre of wall, or roughly 0.02 m³ once you include frogs and droppings. A 20 kg bag of premixed mortar makes roughly 0.01–0.012 m³, so one bag covers about 0.55–0.6 m² of wall, or roughly 25–30 bricks. Check the yield printed on your bag.
That matches the brick calculator example for the same wall: about 887 bricks at 25–30 bricks per bag is 30–35 bags.
For larger jobs, site-mixed mortar is cheaper. General brickwork in Australia commonly uses a 1 : 1 : 6 mix (cement : lime : sand) by volume, while stronger or more exposed work may need 1 : 0.5 : 4.5. Follow your plans or the brick manufacturer's recommendation. Lime makes the mortar easier to work and more durable.
Roughly 0.4–0.5 m³ of mortar for standard bricks, or about 35–40 bags of 20 kg premix.
A common general-purpose mix is 1 part cement, 1 part lime and 6 parts sand by volume, but follow your project's specification.
Yes. Enter the rendered area and the coverage per bag at your render thickness, which is printed on the render bag.