Building a DIY Compost Bin

Tom Roberts from Portland, Oregon USA recently built a DIY compost bin using a plan from Lowe’s.com How-To Libary. Composting is a great way of reusing your kitchen scraps and garden rubbish and it’s fantastic for your garden. This two-bin composting system can be built by one person in about five hours. This DIY compost bin holds one ton of properly moistened yard waste.

You will need:

• Lumber

  5 x 2″x2″ x8′ lumber
  5 x 4″x2″ x12′ lumber
  3 x 6″x2″ x12′ lumber
  6 x 6″x5/4″ x12′ lumber
  All lumber needs to be treated for outdoor use

  Tools

  Drill/Driver
  2 x Clamps with at least 6” Jaws
  Framing square
  Chisel
  Claw hammer
  Circular saw

• Parts

  5′ #12 Jack Chain
  15′ 36″-wide Hardware Cloth
  1 x 1-LB box 3/4″ Fencing Staples
  1 x 1-LB box 3 1/2″ 16d galvanized lumber nails
  2 x 1-LB boxes 2 1/2″ 8d galvanized lumber nails
  8 x 2″x5/8″ corner irons
  1 x 100-count box 2 1/2″ galvanized deck screws
  1 x 100-count box 1 1/4″ galvanized deck screws
  4 x 3 1/2″ tee hinges
  2 x 5″ turning hasps
  12 x 3 1/2″x1/4″ carriage bolts, nuts, and washers
  12 x 4 1/2″x1/4″ carriage bolts, nuts and washers

Step by Step Instructions:

Step 1: The Frame

• Cut 3 x 2″ x 4″ x 5’9″ for joists.
• Cut 2 x 2″ x 4″ x 33″ for headers.
• Mark centers of headers. That is where you will nail the center joist.
• Butt end nail headers to the three joists, overlapping the joists at the ends.

When this step is complete, you should have a 6′ by 33″ rectangle with a joist down the center.

[b2t]

Step 2: The Posts

• Cut 3 x 2″ x 4″ x 34″ for rear posts.
• Cut 3 x 5/4″ x 6″ x 34″ for front posts.
• Using a circular saw, cut a 3/4” deep notch 1 1/2″ from one end of each 2″x 4″.
• Chisel out the waste to create a 1 1/2″ x 3/4″ notch on one end of each rear post.

[b2t]

Step 3: Post Installation

• Clamp the two outer rear posts to the rear corners of the frame. The bottom ends should be flush with the bottom. The notch should be up and facing inward.
• Using a framing square, make sure the posts are all perpendicular to the frame.
• Using 2 x 3 1/2″ x 1/4″ carriage bolts, nuts and washers, fasten each 2″ x 4″ to the base.
• Do the same to the two outer front posts, assembling them to the two front corners of the frame. There are no notches on these posts.
• To install middle front and middle rear posts, mark the center of the front and rear joists and the centers of the two remaining posts. Using 2 x 3 1/2″ x 1/4″ carriage bolts, nuts and washers, fasten the front middle post to the center of the front joist, perpendicular to the base. Repeat for middle rear post.

[b2t]

Step 4: The Floor

• Cut 12 x 2″ x 6″ x 34 1/2″ for floorboards.
• Cut a 3 1/2″ x 1 1/2″ notch in one corner of one floorboard. Starting on the left side with the notched board fitted around the left rear post, line up your floorboards widthwise across the base and flush with the front of the frame. (The boards will overhang the back of the frame). Leave 1/8″ between boards.
• Notch the center floorboard to fit around the center rear post. Since a 2″ x 6″ is actually 5 1/2″ wide, you will have a 3 5/8″ gap after lining up the floorboards.

Cut one piece of 2″ x 4″ x 33″. Lay this floorboard along the right side between the front and rear posts. Using 8d galvanized nails, secure floorboards to frame.

[b2t]

Step 5: The Back

• Cut 5 x 5/4″ x 6″ x 6′ for back slats.
• Starting at the bottom and spacing them 1/4″ apart, secure back slats to rear posts with 2 1/2″ galvanized #8 deck screws. The ends of the slats should be flush with the sides of the rear posts.

[b2t]

Step 6: Front Door Side Runners

• Cut 3 x 2″ x 2″ x 29 1/2″.
• Cut 3 x 2″ x 4″ x 27 1/4″.
• For side runners, stand each 2″ x 2″ upright behind each (5/4″ x 6″ x 34″) front post, flush with outer edge. Stand each 2″ x 4″ behind a 2″ x 2″, again flush with the outer edge of the front post.
• Clamp them together and drill two 1/4″ holes through all three boards, 6″ from top and 10″ from bottom. Join the three boards with 4 1/2″ x 1/4″ carriage bolts, nuts and flat washers.
• This forms a sandwich with a track in the middle (see illustration). Repeat for other side.

[b2t]

Step 7: Front Door Middle Runners

• Mark centers of 5/4″ x 6″ middle post, 2″ x 2″ and 2″ x 4″.
• Clamp the three boards together at the centers to form left and right center channels.
• Drill 1/4″ holes through the three boards 6” from the top and bottom of the middle post assembly. Join them with 2 x 4 1/2″ x 1/4″ carriage bolts, nuts and flat washers.

[b2t]

Step 8: Runner Top Rails

• Cut 3 x 2″ x 4″ x 32″ for top rails of runner assemblies.
• Set a top rail into the notch at the top of each rear post and across to the top of each inner front post (2″x 4″).
• Using 4 x #8 2 1/2″ deck screws, join each of the top rails to the tops of the front and rear posts.

[b2t]

Step 9: Front Door Slats

• Cut 10 x 5/4″ x 6″ x 33 1/4″. Screw 2 x #6 1 1/4″ deck screws into the bottom edge of each of the 10 boards (one on each side), leaving about 1/4″ of each screw protruding.
• Check that the slat’s slide easily in the runners. If they do not, your posts are not 100% perpendicular to your joists. You should still be able to push your posts slightly to adjust them. Using a framing square, make sure the posts are perpendicular to the frame.
• Using 16d nails, nail them to the floorboards.

[b2t]

Step 10: Hardware Cloth Partitions

• To complete the middle partition, cut one piece of 2″ x 4″ x 30″ for the middle bottom rail. Nail it to the central floorboard with 8d nails, between the front and rear middle posts.
• Cut one 31 ” x 34″ piece of 1/4″ hardware cloth. Using 3/4″ galvanized fencing staples every four inches, secure hardware cloth to one side of the middle frame.
• Cut 2 x 36″ x 33″ x 1/4″ hardware cloth. Fold one inch in from each edge to eliminate jagged edges. Using 3/4″ galvanized fencing staples every four inches, secure hardware cloth to the right and left sides of the compost system.

[b2t]

Step 11: Rear Rail

Cut 1 x 2″ x 4″ x 6′ for top rear rail. Fasten to the top of the rear posts, using 16d nails.

[b2t]

Step 12: Lids

• Cut 4 x 2″ x 2″ x 32″ for lid sides.
• Cut 6 x 2″ x 2″ x 31 3/4″ for lid cross-members.
• Mark the centers of the four lid sides. Using 2 1/2″ deck screws, fasten two lid sides to two lid cross-members to form a square (see illustration). Secure third cross-member to the centers of the two lid sides to reinforce the lids.
• Further reinforce the lids by adding 2″ x 5/8″ corner irons to insides of each of the corners see illustration below).
• Cut 2 x 36″ x 33″ x 1/4″ hardware cloth. Fold one inch in from each edge to eliminate jagged edges. Using fencing staples, secure hardware cloth to the tops of lids.

[b2t]

Step 13: Attaching Lids

• Secure the lids to the top rear rail, using 2 x 3 1/2″ tee hinges per lid.
• Using fencing staples, secure one 30″ piece of #12 jack chain to the inside edge of each lid and to the inside of each side rail at about the middle of the rail.
• Complete the lids by fastening a 5″ turning hasp to the middle of each lid and the top front door slat (see assembly illustration – Steps 11 & 12).

[b2t]

Congratulations You Have Now Built Your Own Compost Bin!