How to Build a Compost Bin: 2 DIY Alternatives

Everyone knows the benefits of using compost in their gardens, but nobody wants to look at a compost pile! One solution is a pre-fab compost bin made of plastic, but there are affordable do-it-yourself alternatives.

Most prefab units are compact in size and have removable lids that allow you to add material to the compost. The design allows plenty of air and water to get into the mix, so organic material can properly decompose. The only real work included involved is occasionally stirring or rotating the compost.

But quality prefab compost bins can cost a pretty penny — $40 to $100, or even more. That’s why many people go the DIY route.

Wood compost bin, seen near a brick fence in a backyard
Building a wood compost bin will save you a lot of money compared to purchasing a prefab bin. (©Ket Sang Tai, Adobe Stock Photos)

Wooden DIY Compost Bin

Composting lawn and garden waste is a great way to obtain organic material for your garden while reducing the environmentally negative aspects of trucking yard waste to the landfill.

This wooden DIY compost bin is easy to build and made from pressure-treated wood so it will last for many years to come. It has a removable top along with a hinged door on one end for easy access when filling the bin and removing compost.

While you can make your compost bin any size desired, the one we built was 2 feet wide by 3 feet long by 30 inches high. Pressure-treated 4-by-4 posts were used for the corners and 5/4-by-6 treated lumber for the sides and top.

Be sure to leave gaps between the boards to allow for air to circulate in the bin.

Here’s how to go about building a compost bin for your garden.

Tools:

  • Tape measure and pencil
  • Square
  • Safety glasses and earplugs
  • Level
  • Circular saw
  • Drill/driver
  • Drill and screwdriver bits
  • Post hole digger

Materials:

  • 2 – 4” x 4” x 8’ pressure-treated pine
  • 9 – 5/4” x 6” x 8’ pressure-treated pine
  • 1 – pair hinges
  • 1 – screen door latch or barrel bolt
  • Corrosion-resistant deck screws

Cutting List:

  • Corner Posts: 2 – 3½” x 3½” x 42”
  • Top Boards: 4 – 1” x 5½” x 38”
  • Top Cleats: 2 – 1” x 2” x 22”
  • Side Boards: 10 – 1” x 5½” x 36”
  • End Boards: 10 – 1” x 5½” x 24”
  • Door Cleats: 2 – 1” x 2” x 17½”

Building Note:

Pressure-treated wood is often slightly thicker and wider than standard dimension lumber and may require minor adjustments to the lengths on the cutting list.

Building the Compost Bin

  1. Cut the posts square and to length.

2. Cut the side, end and top boards square and to length.

3. Attach a sideboard flush with the end and edges of two of the posts using screws. Check to see that the board is square with the posts.

4. Position each of the other four sideboards, using 5/8” spacer blocks, and attach them to the posts with screws. Repeat this process to assemble the other side.

5. Dig four holes with a post hole digger for the corner posts.

6. Set the side units in the holes so the outside of the boards are 2 feet apart at each end. Ensure the sides are level and plumb, then loosely fill the holes with dirt.

7. Screw the top end boards to the posts, positioning them flush with the top of the post and aligned with the outside of the sides. Use the spacer blocks to position the remaining boards on the back end of the compost bin, and attach them with screws.

8. Rip the cleats from a piece of leftover 5/4” lumber and screw three of the end boards together to form the door. Use the spacer blocks to position the boards the correct distance apart.

9. Attach the hinges to the door and mount the door on the end board of the compost bin. Attach the bottom end board below the door using a screen door latch or barrel bolt to hold it closed. Pack down the dirt in the holes.

10. Assemble the top of the bin by screwing the top boards to cleats so that the outside boards are spaced 24” apart with an even gap between each of the other boards.

Finally, fill the compost bin with leaves, grass clippings, and other lawn and garden waste.

The amount of time it takes to turn the waste into compost will vary depending on the materials used, the outside temperature, and the humidity.

To speed up decomposition, turn the pile with a pitchfork from time to time and keep the mix damp by wetting it down if it dries out.

Remove the compost from the door on the end of the bin when it is ready.


Joe Truini makes a compost bin from a trash can

Repurposing a Trash Can into a Compost Bin

Composting bins can be expensive, so my buddy Joe Truini decided to make one from an old plastic trash can.

To tackle this project, drill 5/8-inch holes on the bottom and outside of the can (about eight to 10 of them) for drainage and ventilation.

Next, drill the same holes — 5/8 inch in diameter — all the way around the outside of the trash can, including the bottom of the can. Space them 6 to 8 inches apart. These holes are necessary so air can enter the trash can and break down the organic matter.

Set the bin on blocks or bricks, so the air can circulate.

Finally, don’t forget to mix your compost! Since the trash can has a lid, just snap it on, turn the trash can on its side, and roll the trash can horizontally.

Watch the video (above) for the tutorial! 


Further Information

1 COMMENT

  1. Thank you ,! So much for this information . I already have most of the materials. Mainly, I just needed the visual . I’ve used garbage cans to hold my compost, and I really like the wood box design you had . Thanks again !

LEAVE A REPLY

Please enter your comment!
Please enter your name here