Estimate brick/block mortar or tile mortar (thinset), plus material cost — metric or imperial.
Enter 0 for a dry-stacked joint (no mortar). Joint widths commonly used are around 10mm (3/8in), but confirm against your project's specification. Geometric planning estimate based on repeating rectangular units and uniform bed/head joints.
Unit waste (cuts/breakage) and mortar waste (spillage/tooling losses) are applied separately, since they don't move together.
2100 kg/m³ (~130 lb/ft³) is a typical planning estimate for mixed masonry mortar. Adjust for your specific product/mix (Type N, S or M).
Leave at 0 to see total weight only, without a bag count.
Enter a price to see an estimated cost for this mode's bags directly in the results.
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Choose Brick/Block Mortar for masonry walls, or Tile Mortar for thinset under tile. On the Brick/Block tab, enter your wall size, unit size (or pick a common preset) and joint width, optionally subtract door/window openings, and set separate waste allowances for units and mortar - it calculates both the purchase unit quantity and mortar volume. On the Tile Mortar tab, enter your tiled area and your product's coverage per bag from its label. Confirm density and bag weight against your specific product for an accurate bag count, and enter a price per bag on either tab (or check the Cost tab) for a material cost estimate.
Mortar fills the joints between bricks or blocks. The joint area (as a fraction of the wall face) depends on your unit size and joint width, and mortar volume is that joint fraction spread across the net wall area (gross area minus any openings) and thickness. Units and mortar each get their own waste allowance, applied separately, so you can see the base (theoretical) quantity alongside the purchase quantity for both.
This is a geometric planning estimate based on repeating rectangular masonry units and uniform bed/head joints - it works the same way for brick or concrete block (CMU). Actual mortar usage can differ because of unit shape, hollow or perforated units, frogs, incomplete perimeter joints, joint construction, workmanship and site losses.
Thinset tile mortar is trowelled on and combed into ridges with a notched trowel rather than filling a fixed joint volume, so its coverage per bag depends on trowel notch size and tile size - this is normally printed on the product bag or trowel guide rather than derivable from simple geometry. The Tile Mortar tab uses your entered coverage figure directly.
The Brick/Block tab converts mortar volume to weight using a density figure you can adjust, then to a bag count using your product's bag weight. Mortar density varies by mix type (Type N, S or M, or a manufacturer's pre-blended product), so the default here is a typical planning estimate only. The Cost tab multiplies the calculated bag counts by your entered prices for a material-only estimate.
Brick/block mortar. A 6m × 2m wall (12 m² gross, no openings), 100mm thick, using 215×65mm bricks with a 10mm joint: the base requirement is 712 bricks and 0.206 m³ (206 L) of mortar. Applying a 5% brick/block waste allowance gives a purchase quantity of 748 bricks; applying a separate 10% mortar waste allowance gives a purchase volume of 0.227 m³ (227 L), weighing about 476.4kg at 2100 kg/m³, or 20 bags at 25kg per bag.
Tile mortar. A 20 m² floor with a bag covering 5 m² and 10% waste: adjusted planning area = 22 m², needing CEILING(22 ÷ 5) = 5 bags.
The most common mistake is applying the brick/block joint-geometry method to tile mortar, or vice versa - the two are fundamentally different calculations (fixed joint volume versus trowelled coverage) and mixing them up produces an inaccurate estimate. Another frequent error is ignoring joint width's effect on quantity - a wider joint or smaller masonry unit needs proportionally more mortar per square foot than a narrow joint or large unit. It's also worth confirming mortar type (Type N, S or M) against your project's engineering requirements, since density and strength both vary by mix.
This calculator estimates material quantity from the dimensions, density and coverage you enter. It is not tied to any specific manufacturer's coverage chart, does not check structural adequacy, reinforcement requirements, mortar type suitability, or building code compliance, and does not account for substrate preparation, open time or cure time for tile mortar. Density and bag weight defaults shown are typical planning estimates only - confirm your specific product and project requirements separately.
Mortar fills the joints between bricks or blocks, so the volume needed depends on your net wall area (gross area minus any door/window openings), unit size, joint width and wall thickness. This is a geometric planning estimate based on repeating rectangular units and uniform joints - use the Brick/Block Mortar tab above with your wall and unit dimensions for an automatic estimate of both unit count and mortar volume, each with its own waste allowance.
Divide your net wall area (gross area minus any openings) by the footprint of one brick or block (its face size plus the mortar joint) and round up for the base quantity, then apply your brick/block waste allowance separately and round up again for the purchase quantity. The Brick/Block Mortar tab above calculates this alongside the mortar volume.
Thinset tile mortar is trowelled on and combed into ridges rather than filling a fixed joint volume, so coverage per bag depends on your trowel notch size and tile size and is printed on the product bag. The Tile Mortar tab above uses your entered coverage per bag rather than a geometric joint calculation.
Mortar cost depends on type (masonry mortar, thinset, type S/N/M mixes), brand and local prices. Use the Cost tab above with your own bag price for a material estimate specific to your project; installation labour is priced separately.
Mortar types differ mainly in compressive strength and flexibility, driven by their cement-to-lime ratio - Type N is a common general-purpose mix, Type S is stronger and used for below-grade or structural work, and Type M is the strongest, used for heavy structural loads. Check your project's engineering requirements or building code for the correct type.
Yes - wider joints need proportionally more mortar per square foot of wall, and the effect is larger for smaller masonry units since joints make up a bigger share of a small unit's footprint than a large one.
Yes - the Brick/Block Mortar tab uses the same joint-geometry calculation for either. Choose a common brick or block/CMU size preset for a quick start, or select Custom and enter your specific unit's face dimensions and joint width - dimensions are always shown so you can confirm or adjust them.
Breakage and cuts affect the number of units you buy, while spillage and tooling losses affect mortar differently, so this calculator applies separate waste allowances to each rather than one blended percentage. You can see both the base (theoretical) quantity and the purchase quantity for units and mortar.
Yes - add each opening's width, height and quantity in the Openings section on the Brick/Block Mortar tab. The calculator subtracts the total opening area from your gross wall area and uses the resulting net area for both unit and mortar quantities.