For circular fire pit you need to gradually set the first layer of cinder blocks around the circle.
Cinder block fire pit safe.
Porous rock non treated river rocks and also even cinder blocks must not be used inside a fire pit.
When positioned near intense heat they can explode.
After all rows of cinder blocks are in place add a three to four inch layer of gravel to cover soil and provide drainage.
Materials used in fire pits need to be thoroughly considered.
About every 3 feet turn one of the blocks at a slight angle to make an opening for air to get into the pit.
Do you need to use mortar if you re building one.
Place a second layer of cinder blocks on top of the first layer spanning the spaces between the blocks in the first row.
To help the drainage add 3 inches of gravel to the bottom of the fire pit.
For a square fire pit place the cinder blocks side by side instead.
Make sure that the hole in the blocks facing upward.
This creates greater stability for the fire circle.
If you are planning to build temporary fire pit all you need to do is stacking the cinder blocks.
Plan to install your fire pit on a patch of level ground in an open area of the yard that s at least 15 feet from other.
Conventional structure bricks will ultimately crack and require replacing gradually.
Don t position fire pits in hazard prone zones with unfavorable winds.