Cinder Blocks Explained

Cinder Blocks Explained

Cinder block sizes vary and many different shapes are available for your outdoor projects.  There are short ones, tall ones, solid ones and some are made with holes/voids.  Not only are they different sizes, but some that are classified with the same dimensions can be slightly different allowing them to be used in a different manner.

You can build outdoor structures such as fireplaces, kitchen, and pizza ovens using primarily the blocks that are described in this article.  Just for a bit of clarification, most people will call them cinder blocks but there is a slightly more technical term for them.  They are sometimes referred to as concrete masonry units (CMU) by the folks that make them and sell them.  When shopping for these blocks, you only need to call them cinder blocks though and know a little about how they are sized.  The cinder blocks sold in the United States are sized in inches.

Cinder Blocks and Sizes Explained

8x8x16 Block

8x8x16 block

The most common cinder block is an 8x8x16 as seen in the adjacent picture.  These measurements are the depth, height, and width respectively.  Most construction projects, needing any structural integrity, will be built using this size block. These blocks have voids, designed to be filled with concrete, which provides great strength.

 

 

8x8x8 Block

8x8x8 block

These 8x8x8 cinder blocks are perfect cubes that are widely used in conjunction with the 8x8x16 cinder blocks.  These blocks also have voids which allow them to be filled with concrete.

Some have notches manufactured into them for rebar, but the notch will not be used most of the time.  When you are building using a running bond/staggered pattern, these will certainly be useful.

 

8x4x16 block

8x4x16 block

An 8x4x16 cinder block is half as tall as standard 8x8x16 cinder blocks, so they are very good to incorporate into your structure. These cinder blocks are used as a transition block when only a little bit of height is needed as they are only 4” tall.  These blocks also have voids.

 

 

 

4x8x16 block

4" block used for your outdoor fireplace
4x8x16

Occasionally, you will need a cinder block that is only 4” in depth.  These cinder blocks are measured 4x8x16. They have much smaller voids in them which makes them harder to fill with concrete.

A lot of cinder block walls are constructed using these blocks.

 

 

 

8x2x16 cap block

Use these cinder blocks for finish work and solid surfaces.
8x2x16 cap block

One of the last widely used cinder blocks is an 8x2x16 cap block.  When you only need to add a couple inches to your structure or to close off a section, you will use these blocks. These cinder blocks are solid and are also used when a flat surface is needed for finish work.

If you are interested in building an outdoor fireplace or kitchen there are great ways of building them.  Cinder blocks are just one way of constructing them, but it’s a fantastic way to build a structure with great integrity and strength.  Visit www.backyardflare.com for great outdoor fireplace designs, ideas, and DIY construction plans.