A few weeks ago a reader wanted to know about brick foundations. She has an ambitious desire to build a small 900-square-foot house by herself. She is well aware of her physical limitations and asked me if it was possible for her to construct the foundation using standard brick. She had tried to lift an 8-by-8-by-16-inch concrete block and discovered those were too heavy. She feels she could handle brick. She wondered what she needs to know to build a strong brick foundation.
From time to time you’ll hear me say, “You don’t know what you don’t know.” When you apply this to your life experience about all things building, it’s easy to fall into a trap where you feel there are just one or two ways to do something.
Take house foundations, for example. You may live in a part of the country where building contractors use concrete or precast concrete block. If you don’t do research about foundation types, you might conclude that there are just two ways to build a foundation.
But travel to other parts of the United States or the world, and you’ll quickly discover that there are many ways to build foundations that last generations. Each time I go into town to get groceries, I pass at least five old houses that have stacked stone foundations with no mortar between the stones! The builder just chinked the gaps between stones with smaller stones. Most of these houses were built in the mid-1800s and they look sound to me.
In Ashland, New Hampshire, the restored railroad train station, built around the 1860s, sits on top of a distinctive brick foundation. The foundation dates back to 1891, when the station was moved about 100 feet.
The train depot’s foundation is in fantastic shape to this day with no signs whatsoever of structural cracks or failure. It could use a little tuckpointing, but that’s a minor repair. My reader’s dream is going to come true!
That said, it’s important to realize not all bricks are the same. Different varieties can have different solidity depending on how long bricks baked in the kiln and the kiln’s firing temperature. You can make bricks hard and durable enough to pave streets. Just visit Athens, Ohio, to see brick streets that have withstood heavy trucks and brutal winters for decades.
My reader should use a nice strong brick. I told her to go to the Brick Industry Association (BIA) website and download “Specifications for and Classification of Brick,” one of the series of Technical Notes on Brick Construction that the BIA publishes. This simple-to-read, free document shares the best brick to use in a structural situation such as her foundation. She should use a brick that’s rated for severe weathering.
I then shared with her that she should look at the entire list of free Technical Notes PDFs offered by the BIA. They contain a wealth of information about how to install brick of all types.
You should also follow these steps if you’re planning on building a brick-veneer home. A vast majority of brick-veneer homes here in the U. S. , based on my observations, are built incorrectly. Homeowners routinely complain of water leaks. The BIA knows how to capture and control water that penetrates brick and mortar.
I recommended that she use steel for reinforcement in her brick walls. You can buy affordable pieces of reinforcing steel that add enormous strength to brick walls. This steel fabric comes in different widths and is made from two parallel pieces of thin wire measured about an inch less in width than the brick wall. In between the two parallel pieces of wire is additional wire resembling
a continuous strip of the letter W, with the tips of the letters touching one another.
This steel is only about 1/16 inch thick and you lay it directly on top of a course of brick. You then put the mortar for the next row on the wire, just as you would a course without the steel. The BIA Technical Notes provide advice on spacing, but I told her to do it every 8 inches for extra strength.
The thickness of brick foundation walls is important. If the foundation walls exceed 6 feet, I’d makethe walls 12 inches thick. You only get one chance to get this right. If the walls are long, every 12 feet I’d add a brick buttress that’s 8 inches thick and 2 feet long. Cathedral builders in Europe
knew the benefits of buttresses: They’re easy to install and add enormous strength to walls, preventing them from collapse.
The last piece of advice I suggested was that she build a low, experimental wall so she can practice laying brick. It’s not that hard to do. It just requires the three D’s: diligence, determination and discipline. You can do it, too! I’d love for you to send me photos of any brick wall you build.
Tim Carter has worked as a home improvement professional for more than 30 years. To submit a question or to learn more, visit AsktheBuilder.com.