Brick Wall Calculator

Calculate exact brick count for any wall — single wythe, double wythe, with or without openings. Standard modular, queen, king brick sizes.

Wall + brick dimensions

Bricks needed (with 10% waste)

This calculator gives you bricks for a single-wythe wall (one layer thick). For double-wythe load-bearing walls, multiply the result by 2. For walls with openings, calculate gross wall area minus opening area, then enter the result.

How brick count is calculated

effective brick area = (brick_length + mortar) × (brick_height + mortar)
count = (wall area ÷ effective brick area) × 1.10 (10% waste)

The “+mortar” treats each brick as occupying its own area plus the surrounding mortar joint. This matches the bricks-per-sq-ft published by every major US brick manufacturer.

Standard brick face sizes

Brick typeFace (L × H)Bricks/sq ft (3/8" joint)
Modular7.625" × 2.25"6.85
Queen7.625" × 2.75"5.85
King9.625" × 2.625"4.85
Engineer Modular7.625" × 2.75"5.85
Roman11.625" × 1.625"6.40
Norwegian11.625" × 2.75"3.85

Modular is the workhorse — that’s the default in the calculator.

Wall thickness by use

Single wythe (~4" thick): Garden walls under 4 ft, decorative screens, brick veneer over wood frame.

Double wythe (~9" thick): Load-bearing residential walls, retaining walls, walls over 6 ft tall.

Reinforced double wythe with grout fill: Walls over 8 ft, walls supporting roof loads, seismic zones.

For double-wythe walls, multiply the calculator result by 2. For walls with brick on both faces and CMU center, use single wythe × 2 + concrete block math.

Subtracting wall openings

For walls with windows or doors, calculate manually:

  1. Gross wall area = length × height
  2. Subtract opening areas (window length × height, door length × height)
  3. Net wall area = gross − sum of openings
  4. Enter the equivalent dimensions in the calculator (e.g. for 100 sq ft net, enter 10 ft × 10 ft)

For openings under 5 sq ft, skip the subtraction — the 10% waste covers it.

Mortar requirements

Plan on 1 bag of mortar per 100 bricks with standard 3/8" joints:

BricksMortar bags (Type N)Sand (cu ft)
1001 bag0.7
5005 bags3.5
1,00010 bags7
2,00020 bags14

Use Type S mortar for load-bearing walls and foundations. Use Type N for above-grade non-structural (most decorative work).

Bond patterns and waste

Different bond patterns require different waste percentages because of cuts:

PatternWasteDescription
Running bond (default)10%Each row offset by half a brick
Stack bond5%All bricks aligned vertically
Common bond10%Running bond + every 5th-7th course header
Flemish bond15%Alternating headers and stretchers
English bond15%Alternating header courses and stretcher courses
Herringbone (decorative)20%Diagonal pattern, lots of cuts

The calculator uses 10% by default — adjust mentally for fancier patterns.

Buying tips

  • Order all from the same lot — color batches vary
  • Inspect on delivery — reject pallets with >5% chips/breaks
  • Store covered — wet bricks are heavy and absorb mortar moisture
  • 10% extra is standard — don’t massively over-order, returns are usually 25% restocking
  • For load-bearing walls, ask for engineer-spec brick — not all bricks are equal under load

When to use mortar vs dry-stack

Mortared brick walls (everything above) need a frost-line foundation and mortar joints. Dry-stacked brick walls (no mortar, sometimes with hidden steel rods) work for short garden walls under 3 ft and need wider bricks for stability. The calculator above is for mortared walls only.

Frequently asked questions

How many bricks for a 20 ft × 6 ft wall?

Single-wythe modular brick (7.625" × 2.25" with 3/8" joint): ~822 bricks + 10% waste = 905 bricks. Double-wythe (two layers): double that. The calculator handles single-wythe automatically.

What's a wythe?

A wythe is one vertical layer of bricks. Single wythe: One brick thick (typically decorative, garden walls). Double wythe: Two bricks thick (load-bearing residential walls). Triple wythe: Three bricks thick (older commercial). For a double-wythe wall, multiply the calculator result by 2.

What thickness wall do I need?

Garden wall (under 4 ft): Single wythe, ~4" thick. Privacy wall (4-6 ft): Single wythe with reinforced piers every 8 ft. Load-bearing wall: Double wythe (~9" thick) minimum. House exterior with cavity: Brick veneer over wood frame, single wythe.

How much mortar will I need?

Roughly 1 bag of Type N mortar per 100 bricks with standard 3/8" joints. For 905 bricks: ~9 bags of mortar plus ~6 cu ft of masonry sand. Use Type S for foundations or load-bearing walls.

Should I subtract openings (windows/doors)?

Yes for openings over 5 sq ft. Calculate gross wall area, then subtract opening area, then plug into the calculator. For openings under 5 sq ft, the 10% waste covers it. The calculator handles a single rectangle — for walls with openings, do the math externally first.