The Guide To Concrete Block Sizes & Types
- srcustommasonry
- Jan 15
- 7 min read
Concrete and cinder blocks are used for countless different types of projects. So, it’s really helpful to understand the range of concrete block sizes and types to unlock their full potential. In this article, we’ll go over the basic types of concrete blocks and their sizes, their benefits, when to use them, and how to choose the right one for your next project. If you need concrete block masonry in Utah, we can help you! We serve the entire Salt Lake area, including downtown, Ogden, Herriman, Lehi, Provo, and more!
Concrete Block Sizes
Concrete blocks are grouped by their nominal size, meaning they’re named by a rounded, simplified measurement rather than their exact physical size. The most familiar example is the standard 8-inch block, but blocks are also available in 4-inch, 6-inch, 10-inch, and 12-inch sizes. These size labels include the mortar joint in the measurement.
Each size category changes the overall feel of a wall. Thicker blocks add obvious mass and rigidity, while thinner blocks feel lighter and quicker to work with. Knowing the general size category helps people picture the scale and weight of the structure before any measurements are taken.
Concrete Block Dimensions
When you get into concrete block dimensions, you’re talking about actual physical measurements. A standard 8-inch concrete block typically measures about 16 inches long, 8 inches tall, and 8 inches deep. This helps keep the layout straightforward and repeatable. Other block sizes follow the same general pattern, just with less depth. A 6-inch block comes in at about 5⅝ inches deep, while a 4-inch block is closer to 3⅝ inches deep. Since the length and height stay the same, blocks stack cleanly and stay aligned as walls go up,
Concrete Blocks Weights
Once you attempt lifting a few of these blocks, it becomes painfully obvious why weight matters. Heavier blocks take much more effort to move and place, which affects how quickly a project comes together and how physically demanding the work feels.
Most standard concrete blocks weigh somewhere in the range people would expect for dense masonry. A typical 8-inch concrete block generally weighs between 30 and 40 pounds, depending on whether it’s solid or hollow. Thinner blocks weigh less, while wider blocks add noticeable heft. That difference adds up fast when you’re moving hundreds of blocks in a day.
Weight also becomes important because some projects call for more mass, while others benefit from lighter materials. For example, a structure that needs extra stability might rely on heavier blocks, while a wall that puts less stress on the base can use lighter ones. Choosing the right weight helps balance strength, labor demands, and long-term performance.
Types of Concrete Blocks
Solid Concrete Blocks
Solid concrete blocks feel sturdy the moment you handle them. They have a dense, heavy build that gives off an undeniable sense of permanence. Once these blocks are in place, they’ll flex and shift very little over time. That firmness is often what people appreciate most about this particular type of block.
Benefits:
Strength and stability
Solid concrete blocks are extremely dense, which gives them excellent load-carrying strength. Once they’re set in place, they resist shifting, cracking, and movement better than lighter block options.
Long-term durability
These blocks hold up well against weather, moisture, and temperature changes. They age slowly and tend to maintain their integrity for decades with very little maintenance.
Sound reduction
Because of their weight and density, solid blocks help reduce noise passing through walls. Spaces built with them usually feel quieter and more insulated from outside sounds.
Hollow Concrete Blocks
Hollow concrete blocks are easier to work with than they look. Even though they appear similar to solid blocks, they feel noticeably lighter when moved. That difference can make a big impact during larger masonry projects.
Benefits:
Lighter weight and easier handling
Their lighter weight makes them easier to lift, carry, and place. That lighter weight reduces fatigue on the crew and can help projects move along faster.
Better stress distribution
The internal cavities help spread pressure more evenly throughout the block. This can reduce cracking over time and allows the structure to handle minor movement without compromising overall stability.
Improved thermal and sound performance
The air spaces inside hollow blocks naturally slow heat and sound transfer. This can help keep interiors more comfortable and reduce noise compared to denser solid walls, without adding extra materials.
Cinder Blocks
Cinder blocks have a slightly different feel than standard concrete blocks. They tend to be lighter and less dense, which is fairly noticeable right away. This comes from the materials blended into the mix during manufacturing.
Because of that lighter makeup, they actually don’t handle long-term wear quite the same. They can show signs of aging sooner when exposed to moisture or harsh conditions. They still last, just not with the same toughness as heavier concrete blocks.
Benefits:
Lighter overall weight
Cinder blocks are lighter than standard concrete blocks, which makes them easier to move and stack. That reduced weight can speed up work and lower physical strain during installation.
Cost-friendly material makeup
Because they often use recycled byproducts like coal ash, cinder blocks are typically more affordable. That can make them an appealing option when budget is a big consideration.
Good performance for low-stress structures
Cinder blocks still provide reliable strength for many applications without the added mass of heavier blocks. When extreme durability is not required, they offer a great balance between strength and weight.
Aerated Concrete Blocks
Aerated concrete blocks surprise a lot of people when they first handle them. They’re much lighter than traditional blocks and have an airy feel about them. However, that lighter feel doesn’t mean they’re fragile, just built differently.
Benefits:
Exceptionally lightweight
Aerated concrete blocks are much lighter than traditional concrete blocks, which makes them easier to lift, cut, and position.
Natural insulation properties
The air pockets inside aerated blocks slow the movement of heat and sound. This helps create more comfortable interior spaces without relying as heavily on added insulation materials.
Consistent and predictable performance
Aerated concrete blocks are manufactured with uniform density throughout. That consistency helps them perform reliably over time, with less risk of uneven wear or weaknesses.
Decorative Concrete Blocks
Decorative concrete blocks are designed to look finished right from the start. They add visual interest and a bit of personality without sacrificing the solid feel people expect from concrete.
Benefits:
Enhanced visual appeal
Decorative concrete blocks add character and texture without sacrificing strength. They offer a finished look that feels intentional rather than purely functional.
Durable surface finishes
These blocks are designed to hold their appearance over time. Quality decorative blocks resist fading, chipping, and surface wear even with ongoing exposure to the elements.
Low maintenance longevity
Once installed, decorative concrete blocks require very little upkeep. Their solid construction helps them stay structurally sound while continuing to look good for years.
What Are Concrete Blocks Used For
Concrete blocks are a great choice when someone wants a structure that stays solid and worry-free for the long haul. They come into play when strength matters, and constant maintenance is not something anyone wants to deal with. People often turn to concrete blocks when they want to build something once and not have to think about it again for several more years.
They’re also a go-to choice when stability and consistency are important. Concrete blocks don’t shift easily, they handle weather well, and they hold their shape over time. For a lot of projects, that peace of mind is just as important as the structure itself.
Best Use Cases
There’s really no limit to the creative ways you can use concrete blocks. We’ve compiled a simple list of the most common ideas:
Structural walls that need to stay strong and stable for decades
Foundations and base walls where long-term support really matters
Retaining walls that hold back soil and handle constant pressure
Garage and workshop walls where durability is more important than appearance
Commercial buildings that need materials built for heavy use
Privacy and boundary walls that feel solid and secure
Utility buildings and storage structures that need minimal upkeep
Areas exposed to weather, where wood or lighter materials would wear out faster
Raised flower beds that need to hold soil without bowing or shifting
Garden borders that stay straight through multiple seasons of watering
Mailbox bases that need extra weight and stability to stay upright through wind and harsh weather
How To Choose the Right Concrete Blocks
If you have a project coming up but aren’t sure what kind of concrete block to use, there are a few questions you can ask yourself to get started. What’s being built, and how hard is it going to be pushed over time? Some projects just need a solid, dependable block, while others benefit from something lighter and easier to handle. Think ahead to how the structure will live day to day. Weather, moisture, and normal movement all matter more than you might expect. Choosing a block that handles those conditions well can save you from cracks, costly repairs, or frustration later on.
At the end of the day, it’s about matching the block to the job. There’s rarely a one-size-fits-all answer. That’s why asking a professional can be really beneficial. Experience fills in the gaps that specs and charts don’t always show.
Concrete Block Sizes & Types Conclusion
When people talk about concrete blocks, it usually comes down to two things: durability and flexibility. They give you the strength you want, while still offering plenty of options in how a project comes together. Making the right choice early means fewer surprises, less maintenance, and a finished structure that still feels solid years down the road.
At S&R Custom Masonry, we’ve been helping people with concrete block and masonry projects for years, and that experience shows in our work. Folks across the Salt Lake Valley turn to us because we’re straightforward, reliable, and we do the job right the first time. We focus on outstanding quality craftsmanship, clear communication, and results that hold up long after the project is finished.
