By: Nicholas Colefield
Brick masonry is one of the oldest manufactured building materials in the world. Bricks have been the building blocks of many of the world’s great treasures, including: the pyramids of Giza, the Roman Colosseum and the Taj Mahal, which has brick masonry lining the interior walls.
Thousands of years ago, bricks were created by mixing clay or mud with straw or dung, and leaving this mixture in the sun to bake. As time progressed, it became possible to cut bricks into specific shapes, or create shapes using rudimentary molds. Around 3500 B.C., firing bricks in kilns began to replace sun baking as a manufacturing method. Brick no longer had to be made in warmer climates or during the summer months, and with the help of the Roman Empire and their mobile kilns, brickmaking was introduced throughout the ancient world.
Over time, buildings constructed of brick began to experience leaks. This widespread water infiltration issue lead to the development of cavity walls. These walls consisted of at least two wythe’s of brick, with an approximate 2” void space between the wythes. This cavity between the two wythes provided an exit point for any moisture entering the first layer of brick. With the creation of the cavity wall, came the idea for a brick with pre-developed voids. The led to the use of concrete masonry units in construction.
Brick-making was introduced to the British colonies in North America during the late 17th century. According to record, the earliest manufactured brick was found in Virginia. As the colonists recognized the strength, durability and versatility of manufactured brick, they began to build mass production centers. One of the first of these facilities was located in Albany, New York. The brick industry had begun its rise. Many brick buildings constructed during colonial times are still around today. Some notable examples include: Tryon Palace in North Carolina and Independence Hall in Philadelphia.
One of the most notable advancements in brickmaking occurred in 1852. Richard VerValan invented a steam powered brick making machine. Before this machine was introduced, workers would force clay into molds by hand. This meant the clay had to be fairly soft, and the brick units would become misshapen when dumped out of the molds. Automating this process allowed a stiffer clay mixture to be used, resulting in more uniformly square-shaped bricks. This streamlined the manufacturing process, exponentially increased production, and led to an industry boom.
During the industry boom in the early to mid 19th century, the town of Haverstraw, NY became one of the largest brick producing towns in the metropolitan area. With over 40 different brickyards, Haverstraw produced over 300 million bricks annually. Haverstraw’s location in the lower Hudson Valley was ideal. The banks of the river contained vast clay deposits, and brick could be easily transported to New York City by schooners and barges. The economy of Haverstraw skyrocketed after New York City lost hundreds of wooden structures in the great fires of 1835 and 1845, and construction materials shifted from timber to brick. Unfortunately, a landslide caused by the excavation of clay devastated the town of Haverstraw on January 8, 1906. A combination of the landslide and the Great Depression to follow would cause all but just a few brickyards to close their doors. The final brickyard would shut down in 1941, marking the end of an era.
Due to the quantity of bricks being produced during the late 20th and early 21st centuries, people began to blame the brick industry for the degradation of land and the destruction of natural resources. Thousands of pounds of clays were being removed from the earth, and the fossil fuels being burned to power kilns were releasing greenhouse gases. In nations without readily available access to fossil fuel, trees were cut down to use as fuel for the kilns.
Over the decades, the brick industry has moved towards more environmentally friendly methods of producing brick, including the use of natural gas as an alternative to fossil fuels. Additionally, waste materials, such as saw dust, are being used as fuel. Bricks made today are heated to much higher temperatures (2000°F), greatly improving their overall strength and quality. After the manufacturing process is complete, bricks are set aside to cool, and then placed in pallets to be sold. Throughout time, brick making has become less of an art, and more of a process. Today’s worldwide brick making industry produces approximately 1.5 trillion bricks annually.