Brick Calculator
Brick count by wall size, bond and waste factor.
Concrete, Masonry & Stone
Mortar Calculator
Enter how many bricks or blocks you are laying, the joint thickness, mortar type and bag size to estimate how much mortar you need and how many bags to buy, with a waste allowance included.
Your result
Sample values17
Bags of mortar
450
Block laid
0.9
Tons of sand
25.5
Cubic feet of mortar
Type N, ⅜ in joints, 10% waste. 80 lb bags.
What to order
| Item | Quantity |
|---|---|
| Mortar mix, 80 lb bags | 17 bags |
| Masonry sand | 0.9 tons |
| Pallets of sand, if bagged | 18 bags |
| Water, approximate | 85 gallons |
Mortar Calculator: Estimate Mortar Volume and Bags for Brick and Block Walls
Before laying bricks or concrete blocks, you need enough mortar for the joints without ordering excessive material. The deep4sol mortar calculator estimates wet mortar volume and the number of bags required for masonry work. It uses the masonry unit type, unit quantity, joint thickness, mortar type, bag size, and a waste allowance.
It helps bricklayers, homeowners, and estimators plan purchases for brickwork and block masonry, where joint geometry and consumption differ.
What Is a Mortar Calculator?
A mortar calculator estimates the material bonding masonry units. Mortar fills horizontal bed joints and vertical head, or perpend, joints. Consumption depends on unit dimensions, joint thickness, and construction method.
Product yield converts volume into bag quantity. The estimate does not establish mortar strength or structural compliance.
Features, Inputs, and Outputs
The calculator supports brick and block masonry, joint thicknesses, mortar types, bag sizes, and waste.
| Input or Output | Meaning |
|---|---|
| Masonry Unit Type | Selected brick or block category |
| Number of Units | Total bricks or blocks to be laid |
| Joint Thickness | Intended mortar thickness between units |
| Waste Percentage | Allowance for spills, losses, and handling |
| Mortar Type | Selected masonry mortar formulation |
| Bag Size | Packaged mortar quantity used for ordering |
| Estimated Mortar Volume | Approximate wet material needed for joints |
| Total Mortar Bags | Rounded-up bag quantity including waste |
Bag weight does not determine wet volume; check the manufacturer’s yield.
How to Use the Mortar Calculator
- Select masonry unit type. Choose the brick or block that matches your project.
- Enter the number of units. Use your brick or block takeoff rather than the overall wall area.
- Specify joint thickness. Enter the intended bed and head joint thickness according to the project specification.
- Choose mortar type. Match the mix designation to the approved construction details.
- Select bag size. Use the package size of the mortar you intend to purchase.
- Include a waste allowance. Account for material left on boards, spilled during handling, or unusable after mixing.
- Check the results. Review estimated mortar volume and the number of complete bags required.
Estimate differing unit sizes and joint specifications separately.
How Is Mortar Quantity Calculated?
Step 1: Estimate Mortar Volume per Unit
For a simplified single-wythe wall of solid rectangular bricks laid in regular courses, the face area occupied by joints per brick module can be estimated as:
Joint Face Area = (L + j) × (H + j) − L × H
- L = Brick length
- H = Brick height
- j = Mortar joint thickness
Multiplying that area by wall thickness, T, estimates the corresponding mortar volume for one brick module:
Mortar per Unit ≈ Joint Face Area × T
All dimensions must use the same unit. This is an idealized geometric method, not a universal formula for hollow blocks, cavity walls, partially filled joints, or unusual bonds.
Step 2: Multiply by Unit Count
Total Mortar Volume = Estimated Mortar Volume per Unit × Number of Units
For hollow concrete blocks, bedding may cover only face shells and specified webs. Use a block-specific estimate.
Step 3: Include Waste
Mortar Volume with Waste = Base Volume × (1 + Waste % ÷ 100)
Waste is additional material for normal installation losses. The percentage should match job conditions, not a universal default.
Step 4: Convert Volume to Bags
Number of Bags = Round Up (Mortar Volume with Waste ÷ Wet Yield per Bag)
Both volume values must be in the same units, such as liters, cubic meters, or cubic feet. Always round up because partially purchased bags are generally not practical.
Worked Example: Mortar for 1,000 Bricks
Consider an illustrative single-wythe wall made from solid rectangular bricks with these dimensions:
- Brick size: 215 × 102.5 × 65 mm
- Joint thickness: 10 mm
- Number of bricks: 1,000
- Waste allowance: 10%
- Assumed wet yield: 15 liters per mortar bag
These dimensions resemble a standard UK brick and joint arrangement described by the Brick Development Association.
1. Convert the Brick Dimensions to Meters
Length = 0.215 m; height = 0.065 m; thickness = 0.1025 m; joint = 0.010 m.
2. Calculate Joint Face Area per Brick
(0.225 × 0.075) − (0.215 × 0.065) = 0.00290 m²
3. Calculate Mortar Volume per Brick
0.00290 × 0.1025 = 0.00029725 m³
4. Calculate Total Mortar Volume
0.00029725 × 1,000 = 0.29725 m³
About 297 liters.
5. Add 10% Waste
0.29725 × 1.10 = 0.32698 m³
About 327 liters.
6. Calculate the Number of Bags
327 ÷ 15 = 21.8
Rounded upward, the estimate is 22 bags if each selected bag genuinely yields 15 liters of wet mortar.
That bag yield is hypothetical and must be replaced with the manufacturer’s figure. Real mortar use may differ because of bonding, joint profiles, and workmanship.
How Joint Thickness Changes Mortar Requirements
Thicker mortar joints generally increase mortar consumption, even if the brick count stays the same. For the same illustrative brick dimensions, the simplified geometry gives:
| Joint Thickness | Estimated Mortar per 1,000 Bricks, Before Waste |
|---|---|
| 8 mm | 0.236 m³ |
| 10 mm | 0.297 m³ |
| 12 mm | 0.359 m³ |
These are geometric comparisons, not prescribed joint sizes. Follow the specified thickness for proper workmanship.
Mortar Requirements for Brick vs. Block Masonry
Brick masonry typically has numerous horizontal and vertical joints because individual bricks are relatively small. Different bond patterns, wall thicknesses, and header courses can affect the amount of mortar required.
Concrete blocks cover a larger face area per unit, but their hollow cores and bedding practices make direct brick-to-block comparisons unreliable. Filling block cores with grout is normally a separate operation, and grout should not be counted as ordinary joint mortar unless the project specification calls for it.
Avoid applying one generic consumption rate to every unit type.
Mortar Types and Bag Yield
Mortar type influences properties such as bond, workability, strength, and durability. In regions using ASTM terminology, common designations include Type N, Type S, and Type M, but the correct selection depends on the project and governing specifications.
- Preblended dry mortar is supplied in bags and mixed with the manufacturer’s stated amount of water.
- Site-batched mortar may use separate cementitious materials and sand, requiring a different purchasing calculation.
- The calculator’s bag result is most directly useful for a packaged product with a known wet yield.
Never equate a 25 kg, 40 lb, or 80 lb bag with a fixed mortar volume without consulting its product data sheet. Different formulations and moisture requirements may produce different yields.
What Affects Mortar Estimate Accuracy?
Unit Dimensions
Actual brick and block sizes can differ from nominal dimensions.
Joint Thickness
Variations in horizontal and vertical joints change consumption.
Bedding Method
Full bedding and face-shell bedding do not use the same volume.
Bond and Wall Construction
Multi-wythe masonry and header courses may require extra mortar.
Joint Finishing
Recessed, raked, or other profiles can change the final volume.
Workmanship and Waste
Spills, dropped mortar, overmixing, and material that hardens before use increase consumption.
Site measurements can refine complex estimates.
Common Mistakes to Avoid
Using the Wrong Unit Count
Mortar requirements should be based on the masonry units actually being installed.
Ignoring Bag Yield
Package weight cannot be converted into wet mortar volume without product-specific information.
Counting Grout as Mortar
Hollow block core filling is different from bedding and head joints.
Adding Waste Twice
Check whether the displayed bag total already includes your entered waste percentage.
Assuming All Mortar Types Are Interchangeable
Material selection should follow the project’s structural and exposure requirements.
The deep4sol mortar calculator estimates volume and bags for brick and block masonry. Confirm specifications and product yield before ordering.
Questions
Frequently Asked Questions
Mortar quantity depends on brick dimensions, joint thickness, wall construction, and bedding method. For the illustrative 215 × 102.5 × 65 mm brick layout with 10 mm joints, the estimate is about 0.297 m³ before waste.
Divide the estimated wet mortar volume, including waste, by the manufacturer’s wet yield per bag. Round the result upward to determine the number of complete bags required.
Yes. Select the appropriate block unit type and enter the quantity, joint thickness, mortar type, bag size, and waste percentage. Hollow block bedding arrangements differ from those used for solid bricks.
Yes. Thicker bed and head joints generally increase mortar consumption. Even a small thickness change can noticeably affect the total volume when hundreds or thousands of masonry units are involved.
No. Mortar bonds masonry units through bed and head joints, while masonry grout is typically used to fill designated block cores and reinforced spaces. They serve different purposes and usually require separate quantity estimates.
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Estimates, not specifications.
Results are based on the values you enter and on typical material
properties. Densities, coverage rates and product sizes vary between
suppliers, so confirm quantities against your supplier's data before
ordering. Structural work must be signed off by a qualified
professional and meet your local building code.