MEASURE ONCE. PLAN YOUR PURCHASE.

Masonry Core Grout Bag calculator.

Convert measured rectangular block-core voids scheduled for filling into grout bags. Enter net void dimensions and deduct known displaced volume; no filling or reinforcement schedule is chosen.

MASONRY

Your inputs

Metres, litres

Use measurements from your plan and properties from your chosen product. Any prefilled values are illustrative.

Selected mixed grout yield per bag

L/bag

Where to get this value

Use the usable coverage or mixed yield printed on your product label for the stated application. Do not substitute bag weight for finished volume.

Your material allowance

Where to get this value

Enter your own allowance. Presets are input shortcuts, not a construction recommendation.

Scheduled core group 1

Clear core width

Where to get this value

Measure this dimension in your plan or on site and use the displayed unit. For irregular shapes, divide the geometry into the supported sections.

Clear core depth

Where to get this value

Measure this dimension in your plan or on site and use the displayed unit. For irregular shapes, divide the geometry into the supported sections.

Filled height per unit

Where to get this value

Measure this dimension in your plan or on site and use the displayed unit. For irregular shapes, divide the geometry into the supported sections.

Filled cores per unit

Scheduled units

Total known displacement in this group

m³

YOUR ESTIMATE

A clear estimate starts here.

Enter your dimensions and product details to see the quantity and purchase breakdown.

CONTINUE YOUR PLAN

Find the next material.

Keep the quantity, then use another tool for the remaining parts of your purchase.

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Formula and assumptions

BEHIND THE NUMBERS

How this calculation works.

Convert measured rectangular block-core voids scheduled for filling into grout bags. Enter net void dimensions and deduct known displaced volume; no filling or reinforcement schedule is chosen. V = Σ[(core width × core depth × filled height × cores per unit × units − known displacement)]; bags = ceil(V × allowance / mixed bag yield).

V = Σ[(core width × core depth × filled height × cores per unit × units − known displacement)]; bags = ceil(V × allowance / mixed bag yield).Calculated with normalised units

A worked example

Illustrative inputs only. Product properties and design dimensions are not recommendations for your project.

Selected mixed grout yield per bag: 10 L/bag
Your material allowance: 0 %
Clear core width: 0.1 m
Clear core depth: 0.1 m
Filled height per unit: 0.2 m
Filled cores per unit: 2
Scheduled units: 20
Total known displacement in this group: 0.01 m³

Mixed grout bags: 7 bags

Clear rectangular void dimensions only. Bond beams and irregular cores require separately measured volume; no grout or reinforcement schedule is selected.

Before you purchase

Use dimensions from your plan and properties from your chosen product. Any design spacing, section or fixing pattern must already be specified.

Counts quantities from an existing supplied specification. Does not design construction, certify safety, recommend application requirements or establish code compliance.

Example dimensions and product properties are illustrative arithmetic inputs only. Obtain actual yield, density and coverage from your selected supplier.

Method: dimensional arithmetic and user-supplied specifications. Software checks: 2026-10-08. Calculation and review policy.