Concrete block compost bin(s)

 

Concrete block can be used to make a 1, 2 or 3-bin compost unit. Block bins are durable, require few tools and can handle large amounts of yard materials. Growing vines around the outside of the bin(s) can soften the industrial appearance of this bin. These plans are for a 1 or 3-bin unit. To make a 2-bin unit, leave off section #3 of the 3-bin unit.

 

Block bins can be used as turning or holding bins. Turning will make compost much faster. There are two ways to use the 3 bin unit as a turning bins. One is to build a compost pile in one end section, transfer materials to the middle and then transfer again to third section. A
second method is to build two compost piles, one in each end section. Transfer materials from one section to the middle section and back to original end section. Repeat process for the pile in the other end section.

 

 

Half blocks can be purchased or split from full blocks. The illustration (right) shows a full concrete block with a central slit between the holes that makes it easy to split into two half blocks. Score each side of the block in the plane of the slit with a chisel. Then use the chisel and a hammer to split the block along the score.

 

Construction Details:

• Select bin site and level ground. Place concrete blocks on ground as shown in the illustration (reverse side of page). Use 11 blocks for 1 bin unit. Use 25 blocks for 3 bin unit. Leave about ½ inch between each block to let in air.
• Add a second layer of blocks, staggering them to increase stability.
  Note: placement of 2 half blocks in 3 bin unit.
• Add a third layer of blocks, again staggering them to increase stability.
• Add the last or top layer, staggering the blocks.
  Note: placement of 2 half blocks in 3 bin unit.
• To make the unit more stable, drive metal posts through the holes in the blocks as shown in diagram on front page.

3-bin ground layer of concrete blocks.

Source: University of Wisconsin–Extension - Solid and Hazardous Waste Education Center