How Well Do You Know Your Home?
In recent months, our homes have become more important than we could ever have imagined. Our place for shelter and respite from the outside world has slowly transformed into our offices, schools, daycares, studios spaces, and more. As more and more aspects of our lives become confined to our homes, we’ve begun to get to know our homes on a deeper, more intimate level.
Yet, how well do we really know our homes? We know all of their quirks and creaks, but do we actually know what’s beyond their surfaces? What materials were used to make your home? Where were those materials sourced from? Or even, how were those materials processed, transported, and fabricated to become the homes we cherish and love?
Unfortunately, answers to these questions are often buried behind the brick facades and long forgotten. In this blog series, we will begin to unravel the hidden pasts of our homes so that we can begin to better understand how to care for our homes and preserve them for future generations. We will work to trace the origins of four core materials used in the construction of the Chicago bungalow, including: brick, concrete, plaster, and wood. We’ll also explore how those materials are extracted, processed, and how, piece by piece, they become our homes.
Depending on when your house was built, this research will, of course, vary slightly, but let’s take a closer look at some of the most common materials. First up: brick!
You’ll be hard pressed to find a city that holds any other construction material in such a high regard as we hold our beloved Chicago Brick.
Tracing the Origin of Chicago Brick
I think we can all agree that brick is the most character-defining material used in the construction of the Chicago bungalow. Bungalows built in Chicago require a more naturally insulated material (brick) as compared to their West Coast counterparts, which were often made with wood or stucco exteriors. Chicago had also been burned by the Chicago Fire, both literally and figuratively, which led us to rely on brick to rebuild our city because it is a more fire-resistant material. You’ll be hard pressed to find a city that holds any other construction material in such a high regard as we hold our beloved Chicago Brick.
But to begin to understand Chicago’s love affair with brick, we must first go back in time to… around 1.6 million years ago. It may be hard to imagine, but at one point, around 85% of Illinois was covered in glaciers that were roughly 3,000 feet thick or twice the height of Willis tower! These glaciers shaped our current landscape and are the sole reason why Illinois’ land is rich with clay—the main mineral needed to make brick.
Glacial ice sheets in the northern hemisphere slowly began to spread outward, eventually covering Northern America as climates across the globe began to cool. Illinois’ famously flat prairie landscape wasn’t always, well, flat. Ice sheets moved and formed glaciers, leveling hills and filling in valleys, eventually giving us the landscape we see today in Illinois.
As those glaciers began to melt around 10,000 years ago, they deposited clay along what we know today as the Great Lakes and the Chicago River. It wasn’t until 1836, with the digging of the Illinois and Michigan Canal, that it was discovered that Illinois’ soil was rich with clay. Shortly after clay pits surfaced all throughout Illinois and the state was on its way to making good use of this precious mineral. By 1915, 10% of all brick made in America was made in Chicago.
This discovery not only catapulted Chicago forward as an industrial city and one of the fastest growing cities in the world, but it maybe, more importantly, gave us the Chicago Brick.
From Mineral to Material
In order to make the brick used in the bungalow’s double-wythe brick walls (the walls are actually comprised of both an interior and exterior brick wall with a small cavity between them), clay was dredged from either the bottom of Lake Michigan or the Chicago River and transported to nearby brickyards where it was processed. The clay was then ground and combined with a mixture of water and sand in order to be shaped.
Once the bricks had been cut, they were set out to dry to remove excess water. This is one of many reasons why brick making and brick laying was seasonal work. Temperatures had to be warm enough to allow the bricks to dry from the sun’s warmth. Then, when the bricks were dry enough, they were fired in a kiln at temperatures between 1,500 and 1,800 degrees. Kilns were heated using coal and would sometimes burn for 24 hours at a time.
During the height of Chicago brick production, there were over 60 brick production companies within Chicago that produced over 700 million bricks annually. Over the years, many smaller brickyards were purchased and consolidated under a few larger companies. Chicago brick production came to a halt when Congress passed the Clean Air Act in 1970, which required manufacturers to bring their kilns and processing facilities up to date to comply with the new requirements. Rather than complying, the Illinois Brick Company, the one remaining brick production company in Chicago, decided to close. That means that true Chicago brick is no longer being produced.
Although brick is a bungalow’s most recognizable trait, oddly enough it probably makes up the smallest volume of material used in the construction process.
From Material to Home
Bungalows often sit on top of a basement and footing made of reinforced concrete, which we’ll explore more in depth in the next blog post. That means there are a number of steps in the construction process before the bungalow's notable brick facade even begins to take shape. The production of mortar is another critical step that is required before the brick exterior is laid.
In the early 1900s, mortar was made with hydrated lime and sand. The limestone was first burned and then dissolved in water, which could take several days to fully dissolve before it was ready to be mixed with sand to form the mortar. When the mortar was ready, bricks were then laid by hand. It’s hard to know just how many hands it took to build your house, but bricklaying has always been a manual process, and the process itself has changed little to this day. An average 1200 sq ft bungalow with a double wythe brick wall could require around 12,000 bricks. Although brick is a bungalow’s most recognizable trait, oddly enough it probably makes up the smallest volume of material used in the construction process.
It took, quite literally, millions of years to produce your bungalow's exterior.
Getting to Know (And Better Appreciate) Your Bungalow’s Brick
If your house was built between 1871 and 1981, it’s highly likely that your house is made of Chicago Brick. But, because Chicago was also a national hub for trade, brick began to come from other parts of the midwest that also had large amounts of clay in their soil like St. Louis and Milwaukee. An easy way to tell is by examining the color of your bungalow’s brick. Chicago Brick is high in limestone and iron which give it a salmon-y pink color. It also contains glacial debris which almost acts as a fingerprint, giving each brick a unique look. Clay from St. Louis has high levels of iron oxide which attribute to a rich red brick. Milwaukee brick is known for its cream colored brick because of clay that is rich with lime and sulfur.
It took, quite literally, millions of years to produce your bungalow's exterior. From the formation of prehistoric glaciers to the subsequent melting of said glaciers, the manufacturing of bricks was taking place long before humans intervened. Brick is often something that we see as a singular item, but in reality is reliant on many other minerals and materials. Try and imagine the expansive story of your home unfold, brick by brick!
Next up in the series, we’ll take a closer look at concrete and plaster!
Sarah Dezember is currently pursuing her Masters in Architecture with an emphasis in Interior Architecture from the School of the Art Institute of Chicago. In this blog series, she uncovers the hidden histories of materials used in our bungalows to help us understand what’s at the heart of our homes.