Mortar Calculator
Find out how many bags of masonry mortar to buy for a number of bricks or blocks, or for a wall area, with a waste allowance and the bag count rounded up.
What you're laying
Use the count from the brick or block calculator, before its breakage allowance — mortar is needed only for the bricks you lay.
Results
To lay 1,000 bricks with a 10% waste allowance, you'll need about 30 80 lb bags of mortar.
Mortar needed
30 bags (80 lb)
That's a typical amount for a garden wall, a barbecue, or a short block wall.
Keep the water and mixing time the same from batch to batch: both sheets say variations in mix water, mix time, curing conditions and finishing will cause color variations.
bricks to lay: 1,000 bricks
Yield per bag (data sheet maximum): up to 37 bricks
Bags at the maximum yield, no waste: 28 bags
Mortar type (per data sheet): Type N
How this works
To find how many bags of mortar you need, divide the number of bricks or blocks by what one bag lays, add a waste allowance, and round up to whole bags. QUIKRETE's data sheets say each 80 lb bag will lay up to 37 standard bricks or 13 standard 8 × 8 × 16 in blocks. Those figures are maximums, so for 1,000 bricks you need 28 bags at the bare maximum and 30 with the 10% default allowance; for 100 blocks, it is 8 and 9 bags.
| To lay | Bags at the published maximum | Bags with 10% waste |
|---|---|---|
| 100 bricks | 3 | 3 |
| 1,000 bricks | 28 | 30 |
| 100 sq ft of brick wall (700 bricks) | 19 | 21 |
| 100 blocks | 8 | 9 |
| 1,000 blocks | 77 | 85 |
| 100 sq ft of block wall (112.5 blocks) | 9 | 10 |
| Product | Mortar type (per sheet) | Published yield |
|---|---|---|
| QUIKRETE Mortar Mix (Type N), 80 lb bag | Type N (ASTM C270) | Each 80 lb (36.2 kg) bag of QUIKRETE Mortar Mix will lay up to 37 standard bricks or 13 standard (8 in by 8 in by 16 in [200 mm by 200 mm by 405 mm]) blocks. |
| QUIKRETE Mason Mix (Type S), 80 lb bag | Type S (ASTM C270) | Each 80 lb (36.3 kg) bag of QUIKRETE Mason Mix will lay up to 37 standard bricks or 13 standard blocks. |
Sources: QUIKRETE Mortar Mix data sheet (No. 1102, revised November 2020) and QUIKRETE Mason Mix #1136 spec data sheet, checked 2026-10-30. Both sheets list a 60 lb bag as well, but neither sheet publishes a 60 lb yield, so this calculator does not estimate 60 lb bags. On mortar type, the sheets say only that Mortar Mix meets ASTM C270 as Type N and Mason Mix as Type S, and both refer you to the appendix of ASTM C270 (printed there as Appendix XI) for choosing the type. The 10% waste allowance is a BuildyWork planning default with no external source claimed. Thin-set for tile is estimated on the thinset calculator, and adhesive for retaining wall caps is out of scope here.
In wall-area mode the calculator first turns the area into a unit count with the same single-wythe rates the brick and block calculators use: 7 bricks per square foot for standard modular brick and 1.125 blocks per square foot for 8 × 16 in block faces, both of which already include the mortar joints. It then divides the count by the units one bag lays, multiplies by 1 plus the waste allowance, and rounds up to a whole bag. Mortar is needed only for units that get laid, so the brick calculator's breakage allowance is not added here. The bag yields are the two data sheets' figures listed above. To count the units first, use the brick calculator or the concrete block calculator; for a hand estimate of bricks, see how many bricks do I need.
Worked example: a brick garden wall
A brick garden wall is 15 ft long and 4 ft high, so its face is 60 sq ft. At 7 bricks per square foot, that is 420 bricks. At up to 37 bricks per 80 lb bag, 420 ÷ 37 ≈ 11.35 bags, which would round up to 12 bags with no allowance at all. With the 10% default waste allowance it is 11.35 × 1.10 ≈ 12.49, rounded up to 13 bags.
A second example: 180 concrete blocks
A block wall needs 180 standard 8 × 8 × 16 in blocks. At up to 13 blocks per 80 lb bag, 180 ÷ 13 ≈ 13.85 bags, or 14 at the bare maximum. With the 10% waste allowance it is 13.85 × 1.10 ≈ 15.23, rounded up to 16 bags.
Common mistakes
Treating “up to 37 bricks” as the average
The data sheets give the most one bag will lay, not a typical figure. Dropped mortar, mortar left in the mixer and a thicker bed all lower the real number, so plan with a waste allowance rather than the bare maximum.
Scaling the 80 lb yield to a 60 lb bag by weight
Neither sheet publishes a yield for the 60 lb bag. Dividing 37 by 80 and multiplying by 60 produces a figure no manufacturer has stated. Read the bag you actually buy.
Counting broken bricks as bricks to mortar
The brick and block calculators add a breakage allowance to the units you buy. Broken units are never laid, so they need no mortar. Enter the count before that allowance, or use the wall-area input here.
Using the block yield for every block
The 13-block figure is stated for standard 8 × 8 × 16 in blocks. Wider, narrower or half-high units take a different amount of mortar per block, and the sheet gives no figure for them.
When this calculator's model stops applying
- Double-wythe walls: the wall-area input counts one layer of brick, as the brick calculator does. For two layers, enter the total brick count instead.
- Queen, king, utility or oversized bricks and non-standard blocks: the sheets publish yields for standard bricks and standard 8 × 8 × 16 in blocks only.
- Grout for filled block cores: grout for reinforced cells is a separate material and is not estimated here.
- Repointing (tuckpointing) an existing wall: the yield is for laying new units, not for filling raked-out joints.
- Tile: thin-set mortar is estimated by area on the thinset calculator, not by bricks per bag.
- Retaining wall caps: cap adhesive is out of scope for this calculator.
FAQ
Can I use 60 lb bags of mortar instead of 80 lb bags?
Yes, but this calculator cannot count them for you. Both QUIKRETE sheets list a 60 lb bag, yet neither sheet publishes a 60 lb yield, so the calculator offers only the 80 lb bag rather than scaling 37 bricks down by weight. If you buy 60 lb bags, use the yield printed on that bag.
Should I use Type N or Type S mortar?
This page does not choose the type for you. QUIKRETE's data sheets say Mortar Mix meets ASTM C270 as Type N and Mason Mix meets ASTM C270 as Type S, and both refer you to the appendix of ASTM C270 for choosing the proper mortar type. The bag count is the same for either product, because both sheets publish the same yield.
Does the 13-block yield apply to 4 in, 6 in or 12 in wide blocks?
No. The Mortar Mix sheet states the 13-block figure for standard 8 in by 8 in by 16 in blocks only and publishes nothing for other sizes. A wider block has a wider bed, so it uses more mortar per block; for those sizes, ask the mortar maker or a mason.
How thick should the mortar bed be?
Both QUIKRETE sheets say to apply a full bed of mortar onto the base, approximately ½ in to ¾ in thick: 13 mm to 19 mm on the Mortar Mix sheet, 12.7 mm to 19.1 mm on the Mason Mix sheet.
How much water goes into an 80 lb bag of mortar?
Follow the sheet for your product. The Mortar Mix sheet says about 5 quarts (4.7 L) per 80 lb bag, with the maximum expected to stay below 6 quarts (5.7 L). The Mason Mix sheet starts at 9 pints (4.3 L) and puts the final water content at 9 to 14 pints (4.3 to 6.6 L) per 80 lb bag.
Is this the right calculator for setting tile?
No. Tile is set with thin-set mortar, which is sold and estimated by coverage area, not by bricks per bag. Use the BuildyWork thinset calculator for tile instead.
Does this cover the adhesive for retaining wall caps?
No. Cap adhesive for segmental retaining walls is a different product with its own coverage, and it is out of scope here. The retaining wall calculator counts the blocks for that wall.
Does the calculator work in metric?
Yes. The unit toggle switches the wall area between square feet and square metres without losing what you entered, and a brick or block count has no unit to switch. The Mortar Mix sheet gives the standard block in metric too: 200 mm by 200 mm by 405 mm.