Cinder blocks and concrete blocks are both used by professionals and do-it-yourselfers for a wide variety of projects. You may be wondering what the difference is between the two as you start your next construction venture. The reality is, there is very little difference between the two, and it really depends on what you’re using the blocks for.
Cinder Block vs. Concrete Block
Cinder blocks and concrete blocks are nearly the same thing. Both of these masonry blocks use the same three ingredients: water, cement, and aggregate. However, the ingredients and percentage of cement and aggregate differ between cinder and concrete blocks, resulting in concrete blocks being much stronger than cinder blocks and more useful for sturdier jobs.
The Ingredients in Concrete and Cinder Blocks
The ingredients in concrete blocks and cinder blocks are relatively similar—water, cement, and aggregate. However, there are some differences between the two blocks, the main being what type of aggregate is used in them and we’ll break that down further.
What Is Cement?
The words ”cement” and “concrete” are frequently used interchangeably, but they are in fact different. Concrete is a composite material that includes cement. Cement is a binder that sets, hardens, and binds materials together. It’s rarely used on its own and it is typically used to bind the aggregates together. Concrete blocks have a higher percentage of cement in them than cinder blocks do.
What Are Aggregates?
The type of aggregates that can be used in blocks varies. Depending on the aggregate that is used, it affects the block’s overall strength. Aggregates that are used to make both cinder and concrete blocks include:
- Crushed stone
- Boiler ashes
- Burned clay
Aggregates are anywhere from 60 to 75 percent of all concrete and cinder blocks so it is important that these aggregates are clean, strong, and hard.
What Are Concrete Blocks?
Concrete blocks are composed of air, water, cement, and aggregates. When these ingredients are mixed together, a chemical reaction occurs and the result is concrete. The only aggregates used in concrete blocks are finely crushed stones or sand—like cement.
Common Uses for Concrete Blocks
- More substantial building projects
- Retaining walls
- Security barriers
The History of Concrete Blocks
The use of concrete dates back centuries. The earliest usage of primitive concrete blocks is attributed to the Romans, Greeks, and Egyptians. Historians even believe that the pyramids were constructed partially out of basic concrete.
As early as 200 A.D., Romans were using concrete mortar. The Romans used materials sourced locally to produce concrete. Roman architecture during this time required sturdy building materials, making concrete a great option for their infrastructure and buildings.
In 1824, modern-day concrete was patented by British cement manufacturer, Joseph Aspdin. The recipe that Aspdin created is what we know as cement today—what he patented is known as Portland cement.
In 1890, Harmon S. Palmer designed the first hollow concrete block in the United States, and by 1900 Palmer patented his design. These concrete blocks were so heavy that one person could not carry them on their own!
While the earliest concrete blocks in the 1700s were cast by hand and a single person could produce about 10 blocks in one hour, Today’s production of concrete blocks is fully automated and thousands of blocks can be manufactured in a single hour.
What Are Cinder Blocks?
Cinder blocks differ from concrete blocks in one important facet. While concrete blocks only use finely crushed stones as the aggregate, cinder blocks use a variety of aggregates with cinder being the most common aggregate used.
The use of cinder, which can be burnt wood or coal, instead of stones like in concrete blocks lightens the block and also reduces the cost of production.
Using coal or wood waste as an ingredient in the production of cinder blocks makes this building material a greener option for those looking to reduce their carbon footprint.
Common Uses for Cinder Blocks
- Flower gardens
- Non-foundational walls
- Outdoor fireplaces
The History of Cinder Blocks
When the main form of heating homes used to be burning wood or coal, there was an excess of cinders. This excess led to the creation of a new type of block in the 1850s. A typical household could produce a great deal of cinder waste in a single winter, making cinder a more affordable aggregate to use.
Which Masonry Block Is Right for My Next Project?
When selecting which block is right for your next project, it’s important to think about what you are building and what is your desired outcome. Cinder blocks are a great choice if you are making a garden or landscaping. If your next project is more structural, like a retaining wall or steps, concrete blocks might be the way to go.
|Concrete Block||Cinder Block|
|Withstand High Pressure||✔️|
|Lighter Weight Block||✔️|
|Used in Smaller Projects||✔️|
|Used in Larger Projects||✔️|
|Requires Less Repair||✔️|
|Uses Ash or Cinder||✔️|
|Uses Stone or Sand||✔️|
Whatever your next project is, you’ll need to know how much concrete or cinder blocks you’ll need to purchase. You can use a concrete calculator to know exactly how many blocks will be used in your next project.
Emily is a freelance writer and teacher. Originally from New York, Emily now lives and works in Europe.