I’m a frugal person with fairly poor DIY skills.
The two don’t always go hand in hand., but it does mean that when I share a composting project (like this pallet bin system), you can be sure it is easy to follow 😉
This one actually came about when a friend told me about a problem he was having with his compost bins (details below).
I thought I could take the standard trash bin compost design and make some improvements.
But first, let’s take a look at the usual way to turn a garbage can into a compost bin.
How to make a basic DIY trashbin composter
- Drill holes in the side of the bin
- Drill holes in the base.
- Clear away any bits of plastic left by the drilling.
- Raise it on bricks.
- Place a lid on it if it is outside.
This is the process my friend followed, but he had a problem with leachate.
(That’s the liquid that comes out of the compost.)
The leachate was spilling out of the side of the compost bin, creating a mess in his polytunnel.
It also meant he couldn’t catch the leachate and use it as a fertilizer.
So we’re going to experiment with a design change that will both improve airflow but make it easier to catch liquid flowing out of the bin.
How to Make A DIY Trashbin Composter with Passive Aeration
What you need:
- 1 trash can (plastic or metal)
- 1 drill with paddle drill bits and smaller drill bits
- Three bricks or stones
- A length of thin PVC Piping (we used one with a 38mm diameter)
- A container to catch leachate
This is a super cheap or even free way to make a compost bin.
I’d recently had some plumbing done in the house, and I asked the plumbers to leave a piece of piping below.
I used an old bin. This had a split in its lid, so it wasn’t much use outside.
(If you don’t have the materials, you can likely find them at the local dump!)
Do note that this was for a polytunnel. If you are making ones for the outdoors I would recommend using a bin with a sealed lid to prevent the compost from getting soaked by the rain.
I found the bricks lying around, so they were also free!
Total cost: $0.00 (if you can find the materials lying around 😉 )
- Turn the bin upside down.
- Drill holes in the bottom.
You have the choice of lots of holes or a few big holes.
We decided to go for four 32mm holes near the center of the bin, to make it easier to slide a container in and catch leachate.
After trying the bin out, I went back and drilled a further large hole in the compost bin to allow the PVC pipe to run through the bottom hole.
We used a 38mm wide circle cutter for this, but it will depend on the size of the PVC pipe you have.
This allows the air to run right through the compost.
I also drilled four small holes in the front of the bin.
That’s because the bin base is raised in the center. I don’t want the liquid to get trapped in the sides and cause anaerobic composting, so this should allow the liquid to drain instead. .
- Drill holes in the PVC piping.
We went for much smaller holes here, using a 6mm drill bit, with each one spaced about 2-3 inches apart.
We also drilled right through the PVC to create 2 holes parallel to each other.
After drilling each hole, we turned the pipe 90 degrees and drilled another hole.
That meant every two-three inches (we used fingers to measure the distance!) we had four holes to maximize airflow.
Note you could also trim the PVC to go just above the height of the bin. However, by avoiding doing this you can use the pipe for a larger compost heap (or bin) in the future.
- Place the bricks where you want the bin to be.
I want to maximize airflow for this setup.
By raising the bin up, I can ensure that air flows under the bin and up through the air holes. To do this, I placed three bricks where I planned to put the bin.
I arranged the bricks in a semi-circle so I could slide a container in and out to catch leachate.
- Place a container in between the bricks.
This is the container that will catch the leachate.
- Place the PVC piping in the bin.
As you do, fit the base of the PVC pipe through the hole.
(The photo below is after I had emptied the compost bin and drilled the second hole, so don’t expect a nice clean bin 😉 )
- Add your material.
You can either add your material all in one go, or gradually over time. Composting is likely to be faster if you add it all in one go, but either way, you will get compost.
After you have added a bit of material, raise the pipe up so it’s still poking through the bottom of the bin, but is raised off the floor. This should maximize airflow.
(I’d suggest not fixing the pipe in permanently, as that could make it more difficult to remove the compost when you are finished with it.)
- Cover the top with straw (optional)
Because my bin is inside the polytunnel and is filled with manure, I decided to cover it with a layer of straw to act as a biofilter.
The idea here is to reduce any odors and reduce the number of flies coming into the polytunnel.
You could also cover it with a layer of sawdust and/or soil or compost.
I also inserted my Reotemp compost thermometer so I can monitor the temperature.
Will it get hot?
I’m going to be experimenting with this bin over the next few months.
One query I have in my head is whether there is too much airflow for hot composting.
After all, air doesn’t just help bacteria, it also conveys heat out of the compost heap.
I’d also like to try the bin with and without the PVC pipe, and see what difference it makes.
Stay tuned, as I’ll post the results here when they’re out.
How could the design be improved?
One way to improve the bin would be to add insulation around the outside.
This can be trickier with some bins, as they have air holes in the outside. But as this bin uses a PVC pipe to provide airflow, covering holes won’t be an issue with this bin.
Do note that if you are using the bin outside, it would be best to use a lid.
If you do, make sure you leave some space between the top of the compost material and the lid to trap air inside.
If you are using PVC pipe, you’ll also need to trim the top to ensure it can fit under the bin lid (but above the compost).
How to use the DIY compost bin
Generally, you use the bin just like you would a regular compost bin.
We’ve gone into detail on this in other guides, but here’s a quick recap.
- Add a mixture of ‘Green’ and ‘Brown’ materials.
- Reduce the size of the material if needed – ideally to one to two inches.
- Add bulking agents to ensure airflow.
- Ensure moisture levels are correct.
- Usually you will need to aerate the compost. However, the PVC pipe should do this for you.
The leachate can be diluted and used as fertilizer, or added back into the compost to keep nutrients.
Composting doesn’t have to be expensive
You really can spend as much or as little as you want on composting.
Some bins are expensive to buy or, depending on the materials you use, to build.
Depending on their design, they can be worth the money if you have it to spare.
But there are also super-easy options which will still turn organic waste into free compsot that will benefit your garden for years to come.
And if I can do it with my super-poor DIY skills, I am sure you can too!
If you have built a DIY bin of your own, I’d love you to share pictures of it with us over on our Facebook page!
How to Make an Easy DIY Pallet Compost Bin
How to Make a Simple DIY Worm Bin
The Ultimate Guide to Making and Using a Three-Bin Compost System (for composting larger amounts of waste)
Composting for a New Generation Review (full of DIY projects like this one!)
Can this compost bin be used outdoors?
Yes, this bin can be used outside, but it is recommended to use a bin with a sealed lid to prevent the compost from getting soaked by the rain. You’ll also need to trim the pipe so that it is covered by the lid.
Can the leachate be used as a fertilizer?
Yes, the leachate can be diluted and used as a liquid fertilizer for plants. Alternatively, it can be added back into the compost bin to keep nutrients and microorganisms in the compost.
Can the PVC piping be permanently fixed in the bin?
Yes, but I wouldn’t, as it may make it more difficult to remove the compost when it is finished. It is better to leave the pipe in place but not fixed, as this will allow for easy removal of the compost and adjustment of the pipe as needed.