Brick Calculator

Brick formula

Wall area (sq ft) = Length x Height - openings
Brick face with joint (sq in) = (Brick length + joint) x (Brick height + joint)
Bricks = Wall area x 144 / Brick face with joint x (1 + waste %)
Mortar bags (80 lb) = Bricks / 37 for modular brick with 3/8 in joints

Worked example

A 30 x 6 ft garden wall with a 3 x 4 ft opening, in queen brick with 3/8 in joints: wall area is 180 - 12 = 168 sq ft. A queen brick with its joint covers (7.625 + 0.375) x (2.75 + 0.375) = 8 x 3.125 = 25 sq in, so 144 / 25 = 5.76 bricks per square foot. 168 x 5.76 = 968 bricks, or 1,017 with 5% waste.

Mortar: a bag lays 37 modular bricks covering 21 sq in each, so it lays about 37 x 21 / 25 = 31 queen bricks. 1,017 / 31 = 33 bags of 80 lb mortar mix.

Quick reference

How to calculate bricks for a wall

Measure the wall length and height and multiply for the face area, then subtract doors and windows. Divide that area, in square inches, by the face of one brick including its mortar joint. A modular brick with a 3/8 inch joint occupies 8 by 2-5/8 inches, or 21 square inches, so one square foot of wall holds 144 / 21 = 6.86 bricks. A 160 square foot wall needs about 1,100 bricks.

This is for a single wythe, which is how brick veneer on a wood-frame house is built. A solid double-wythe wall needs twice as many bricks. Add 5 percent waste for a plain wall and 10 percent when there are many cuts, corners, soldier courses or arches.

Mortar, ties and weight

Premixed mortar in 80 lb bags is the easy option for small jobs: a bag lays about 37 modular bricks. For anything over a few hundred bricks, site-mixed Type N mortar (1 part masonry cement to 2-1/4 to 3 parts sand) is cheaper; roughly 10 bags of masonry cement and three quarters of a cubic yard of sand lay 1,000 bricks with 3/8 inch joints.

Brick veneer needs a corrugated wall tie every 16 inches vertically and 24 inches horizontally, weep holes every 24 to 33 inches along the base, and a 1 inch air space behind the brick. Bricks arrive on cubes of about 500, and a cube of modular brick weighs about 2,300 lb, so plan where the delivery truck can set them down.

Key facts

• A modular brick is 7-5/8 x 3-5/8 x 2-1/4 in; with a 3/8 in joint it lays up to 8 x 4 x 2-2/3 in, so three courses rise exactly 8 in.
• A single-wythe wall takes about 6.9 modular bricks per square foot, usually rounded to 7.
• An 80 lb bag of mortar mix lays about 37 modular bricks; 1,000 bricks need roughly 27 bags.
• Queen and king bricks are larger, so a wall needs about 5.8 or 4.8 bricks per square foot instead of 7.
• A modular brick weighs about 4.5 lb, so 1,000 bricks weigh about 2.25 tons.

Frequently asked questions

Sources and references

• •Technical Note 10, Dimensioning and Estimating Brick Masonry (Brick Industry Association)
• •QUIKRETE Mortar Mix No. 1102 product data sheet (Quikrete)
• •Sakrete Mortar Mix Type N product page (Sakrete)