Terminology

• Brick: fired clay masonry unit; modular actual size 7-5/8 by 3-5/8 by 2-1/4 in., nominal 8 by 4 by 2-2/3 in. with a 3/8 in. joint
• Facing brick: brick for exposed walls; ASTM C216 types FBS, FBX, and FBA
• Grade SW / MW: freeze-thaw resistance grades in ASTM C216
• Shale: fine-grained rock fired with or in place of clay
• Terra cotta: fired clay used for cornices and cladding
• Structural clay tile: hollow fired clay unit
• Frog: recess in a brick face; frogged and hollow designs reduce density

History and demand

First uses in construction

• Before 7500 BC: earliest mudbricks, at Tell Aswad
• About 5000 to 4500 BC: Mesopotamia discovered fired brick; Chengtoushan, China had fired bricks around 4400 BC; Kalibangan, Indus Valley, about 3000 BC
• First half of the 19th century: mechanization began; Henry Clayton's machine made up to 25,000 bricks a day
• Industrial Revolution: brick became preferred over stone for speed and economy
• Mid-20th century: many United States cities replaced brick streets with asphalt; steel and concrete have largely replaced brick in high-rise construction

Sourcing

• China, India, Pakistan, and Bangladesh are among the major producers of fired clay brick; global output is estimated at 1.9 to 4.1 gigatonnes a year (Olsson et al., 2025)

Demand trend

• The industry-wide clay brick EPD captured 32 percent of 2018 production from 13 manufacturers

Composition and production

Raw materials

• Clay and shale: aluminosilicate, free silica (quartz), and decomposed rock
• One proposed optimal mix: silica 50 to 60 percent, alumina 20 to 30 percent, lime 2 to 5 percent, iron oxide up to 7 percent, magnesia under 1 percent

Manufacturing process

• Molded bricks fired at 900 to 1,000°C (1,650 to 1,830°F); color shifts through dark red, purple, and brown or gray at about 1,300°C (2,370°F)
• A continuous Bull's trench kiln fires about 15,000 to 25,000 bricks a day

Product forms

• Brick, structural clay tile, terra cotta, and pavers

Grades and types

• Grade SW and Grade MW: ASTM C216 classes by freeze-thaw resistance
• Types FBS, FBX, FBA: the three ASTM C216 facing brick types

Properties

Physical

• Density (solid clay brick): about 2,000 kg/m³, about 125 lb/ft³; hollow and frogged units are lighter

Mechanical

• Compressive strength: United States bricks range from about 1,000 to 15,000 psi (7 to 103 MPa) by use; common house brick 20 to 40 MPa (2,900 to 5,800 psi)

Standards

Material specifications

• ASTM C216: facing brick (C216-26a active)
• TMS 602: masonry units, mortar, and grout construction requirements
• TMS 504: architectural cast stone

Uses in buildings

Building elements

• Brick Veneer Walls: facing brick
• Ceramic and Porcelain Tile: fired tile bodies
• Clay and Concrete Tile Roofing: clay roof tile
• Lavatories and Sinks, Water Closets and Urinals: vitreous china fixtures
• Site Paving: brick pavers

Pros and cons

Pros

• Range of compressive strengths up to 15,000 psi
• Standard modular size of 7-5/8 by 3-5/8 by 2-1/4 in.
• Fired color is integral to the unit

Cons

• Heavy: about 125 lb/ft³
• Replaced by steel and concrete in high-rise construction
• Strength and grade vary by unit and use

Design considerations

Movement

• Brick expansion joints sized and spaced per BIA Technical Notes 18 and 18A

Finishes and treatments

• Firing color: dark red, purple, brown, or gray by kiln temperature

Sustainability

Embodied carbon

• Industry-wide clay brick EPD (Brick Industry Association, United States and Canada production, cradle to gate); the listed copy expired October 7, 2025 and the value was not retrieved

Manufacturing and cost

Main manufacturers and suppliers

• Glen-Gery
• General Shale
• Acme Brick
• Endicott
• Hohmann and Barnard

Trade association: Brick Industry Association.

Sources

• Wikipedia: Brick, https://en.wikipedia.org/wiki/Brick
• ASTM International: C216-26a facing brick, https://store.astm.org/c0216-26a.html
• BD+C: new industrywide clay brick EPD launched, https://www.bdcnetwork.com/codes-and-standards/news/55163827/new-industrywide-clay-brick-epd-launched
• UpCodes: 2024 IBC Chapter 21 masonry, https://up.codes/viewer/department-of-defense/ibc-2024/chapter/21/masonry
• Wikimedia Commons: Argile de potière 03.jpg, photo by Bamouzou (CC BY-SA 4.0), https://commons.wikimedia.org/wiki/File:Argile_de_potière_03.jpg
• University of Leeds and White Rose: greenhouse gas emissions and decarbonization potential of global fired clay brick production, https://eprints.whiterose.ac.uk/id/eprint/223190/2/olsson-et-al-2025-greenhouse-gas-emissions-and-decarbonization-potential-of-global-fired-clay-brick-production.pdf