Construction & renovation
Mortar calculator
Estimate mortar volume and bags for a brick or block wall. Calculations stay local in the browser and the assumptions are adjustable.
Project settings
Estimate mortar volume, dry-mix weight, and bags for a masonry wall.
Quantity estimate only: adapt the values to the product, the site, and the applicable technical rules.
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How does this tool work?
Estimate mortar volume, dry-mix weight, and bags for a masonry wall. Adjust the assumptions to compare several scenarios before preparing a material order.
The mortar calculator runs entirely in the browser from the dimensions and parameters you enter. The engine subtracts the solid masonry-unit volume from the apparent wall volume, applies the waste allowance, and converts the resulting mortar volume into dry-mix weight and bags. Every result is recalculated when an input changes, so different assumptions can be compared before ordering. The calculation remains a quantity estimate: it does not verify building-code compliance, structural design, or product-specific installation requirements.
Mortar consumption changes significantly with brick or block format and joint thickness. To convert the calculated volume into bags, use the yield stated for the chosen mortar rather than a generic conversion.
How to use this tool
Describe the project
Enter the dimensions and parameters that match the real site.
Adjust assumptions
Match spacing, densities, stock sizes, and waste to the products you plan to use.
Check the quantity
Use the result to prepare an order, then verify it against the relevant technical requirements.
Use cases
Prepare an order
Turn project dimensions into a first mortar quantity to compare with supplier pack sizes and stock lengths.
Compare assumptions
Change dimensions, spacing, density, or waste and immediately see how the required quantity changes.
Check a quotation
Use the intermediate results to verify the order of magnitude of a material quantity in a quote.
Tips and best practices
- Measure the actual site or finished support instead of relying only on drawings.
- Replace the suggested values with the manufacturer or supplier specifications.
- Use a waste allowance that reflects cuts, offcuts, overlaps, and site constraints.
Frequently asked questions
Does this replace structural or technical design?
No. The calculator estimates quantities from geometric inputs. Strength, sections, reinforcement design, spans, and code-required thicknesses must be checked separately.
Why include a waste allowance?
Waste covers some cuts, breakage, offcuts, overlaps, and measurement variation. The appropriate percentage depends on the material, layout, and site.
Can I order from the default values?
The defaults are examples only. Before ordering, replace them with the real dimensions and the technical specifications supplied for the product you will use.
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