Building a Compost Bin


For gardeners, the best dirt comes from compost. It’s easy and free to accumulate food and garden scraps that decompose into highly nutritious soil. However, compost piles and store-bought plastic bins are unattractive and visually disruptive in a natural garden landscape. A cedar wood compost bin with a roof is the ultimate compost bin. Cedar is naturally resistant to rot and rodents, and the natural wood finish complements the garden aesthetic. To top it all off, a stately roof adds functional structure and visual appeal. 


What to Know When Building a Composter with a Roof


When learning how to build a compost bin with a lid, there are a few important things to know. 


Should composters have a roof?


Yes, composters should have a roof. A roof protects the compost from the elements, and is often the most visible part of the structure. A composter with a nice roof is more attractive and durable than a composter with a lid. A plywood lid is flimsy and will quickly rot. A sturdy roof keeps animals out of the compost. 


What makes a good composter roof?


For DIY projects, a good composter roof is affordable and easy to install. To be effective, the roof needs to be sturdy enough to stay in place, and light enough to lift easily. The roof needs to have smooth edges so it is safe to handle. The roof needs to be heat resistant so that it does not get too hot to touch on peak summer days. It also needs to be rust resistant so that it does not degrade overtime. 


Tools & Materials for Building a Composter with Roof



  1. Drill
  2. Hand or circular saw
  3. Pencil
  4. Measuring tape
  5. Sand paper
  6. Staple gun
  7. Protective goggles and gloves



  1. Cedar 1x4 planks
  2. Concrete pavers
  3. Wire sheeting
  4. Staples
  5. Wood screws
  6. Hinges
  7. ONDULINE® ONDURA® roofing sheet
  8. ONDULINE® screws 
  9. Oil lubricant


Steps in Building the Ultimate Composter


  1. The first step is to cut the lumber. Take extra care when measuring, and always measure twice before cutting. 
  2. The second step is to build the base of the composter. If rodents commonly visit your garden, you can use concrete pavers to elevate the wood posts and floor off the ground. Raising the base of the composter can also make shoveling easier. 
  3. From the base, build posts to create a frame. The back of the composter should be higher than the front of the composter to allow for a shed style roof. To allow rain and snow to flow off easily, the slope of the roof should be 3:12 or greater. If your composter has sliding front panels or removable slats, add rails to the front posts. 
  4. Once the base and frame are complete, the next step is to assemble the back and sides. Working one side at a time,  individually add each plank to the frame. Make sure to leave a gap between each plank to allow for air circulation. Even gaps are most attractive. You can use a 1x4 plank turned on its side as a guide. 
  5. Once the back and sides are complete, the fifth step is to attach a wire mesh fabric liner using a staple gun. This will keep the compost contained and facilitate airflow. 
  6. The sixth step is to build dividing walls, if your design includes multiple compartments. The planks for the partitions need to be spaced apart and covered with a wire mesh fabric liner. 
  7. The seventh step is to build the front pieces. There are a few different options. Sliding panels, removable slats, or doors are necessary to access the compost to turn or shovel it as needed. Sliding panels can be built by attaching planks to two battens. Once assembled, the panels slide into tracks built on the frame posts. Removable slats work similarly as sliding panels, but provide the option to incrementally open the front of the composter. Door panels need to be built and framed separately and then attached with hinges and latches. If you would like to omit the gaps between planks to conceal the compost and create a more finished look, drill small holes into the wood for a discrete source of airflow. 
  8. The final step is to build a roofing structure. The roof is the most important part of a compost bin, so this step deserves a dedicated section. 


How to Build a Roofing Structure for Your Compost Bin


  1. The first step is to measure the exact distance between the corner posts to determine the size of the roof frame.
  2. The second step is to use the measurements to build a wood frame that can rest on top of the compost bin and support the roofing material. If the roof is several feet long, a cross beam or multiple cross beams can be used to add additional support. 
  3. The third step is to cut the roofing material to fit on top of the wood frame. A slight overhang of 1 to 2.5 inches can ensure that the rainwater and snow fall off and away from the sides of the composter. Mark the measurements with a pencil. The Onduline ONDURA® roofing sheets can be cut with a utility knife held parallel to the corrugation. If you need to cut across the corrugation, use a hand or circular saw. Use an oil lubricant to smooth the saw cutting. 
  4. The fourth step is to install the roof cover. Unless your composter is extraordinarily large, you are likely using one or less than one ONDURA® roofing sheet. If you are using multiple roofing sheets for an extra large composter, refer to the ONDURA® installation guide for information about layering the panels. To install the roof cover, drive ONDULINE® screws along the edges, through the crown of the corrugation, perpendicular to the roof’s surface so that the rubber washer on the screw snugly contacts the panel without dimpling the material. Be careful to not overdrive the screw. 
  5. The fifth step is to attach the framed roof to the compost bin. Use sturdy hinges, and consider adding a lever to prop the roof open. 


Once your compost bin is complete, it’s time to celebrate! For more DIY inspiration and high-quality roofing and siding materials, visit Onduline’s website