The compost bins are done! (Actually, they were finished about two weeks ago, but I was too busy harvesting to get this post written.)
They are huge, but I think its just the size we need. Here’s a bunch of photos and some details about building this 3 bin composter out of recycled fence materials. The only thing we purchased was $5 in nails (which we bought from our neighbor, who had part of a box leftover from the fence rebuild over Labor Day weekend.)
Here’s a shot of the messy pile of materials we started out with (mostly cedar wood):
Mostly fence slats, but a few good 4x4s and 2x4s mixed in there.
First I cleared the space where the 3 compost bins would be:
Then I came up with a plan that would enable us to build a 3 bin structure using only the reclaimed fencing. (Imagine a poorly drawn sketch on the back of scrap of paper.) Each bin is 4 feet wide by 4 feet deep by 3 feet tall.
I showed my sketch and explained the plan to my husband, and then he jumped right in and got to work.
First he dug holes about 18 inches deep for the main posts of the structure. We used the 4x4s for the main vertical posts in the front (to hopefully keep the side walls from leaning over time), and 2x4s for the back posts (where there would be more support from cross pieces). We didn’t go so far as putting cement in the holes (it just seemed like overkill, plus we didn’t want to spend the money for it).
Luckily we had two 16 foot long 2x4s, which we used as the main horizontal pieces across the back of the composter. Once those were attached, we used 4 foot 2x4s to attach the front 4×4 posts to the rear 2×4 posts. Then the main structure of the composter was done.
The fence slats were ripped in half lengthwise with a table saw. We decided that skinnier slats would allow more air to reach the compost. But then we ended up adding some scrap 2x4s as extra vertical supports in the middle of each wall, which you can see below.
The random looking strips of wood across the front of the bins in the picture above are just scraps used to temporarily hold together the 4x4s and keep things as square as possible while we were screwing and nailing the structure together.
My husband had the idea to make the center walls of the composter “hollow” to allow more air circulation. So there’s a gap in the walls that allows to air to get in, but if compost works its way in there, there’s 2 slats missing at the bottom so we can scoop it out easily.
Here the main body of the composter is done:
As soon as the main structure of the composter was done, I moved the piles of compost in to their new home.
The last part of the project was to construct the front doors for the bins. We used pieces of fence slats that slide down into grooves along the front of the bins. Its kind of hard to describe, but really easy to do, and you can find lots of examples on how to construct it if you browse compost bin designs on the internet.
Pictured below is the “new” pile we’ve been adding things to for the couple of weeks. You can see the hollow wall on the left, which allows more air circulation. You can also see the extra support post that my husband added along the front to ensure the sides don’t lean, buckle, or bow over time. The support post is easily moved when you are removing or adding material.
This side shows the pile of finished compost, which I am currently depleting as the raised beds get turned over, amended, and put to bed for the winter.
On Monday I turned my first pile of compost in the composter. I was surprised how dry it was, given that I had watered the pile thoroughly two weeks ago when I first put this material in there.
The middle bin is about halfway full of the newly turned compost now. I am eager to see if things get cooking in there soon.
I really like how the compost bins turned out. Its nice that the wood matches the already existing fencing in the backyard. Of course I also love that it only cost us $5 plus our time to build it. I have to give most of the credit to my husband, because it wouldn’t have gotten done without my him stepping up and doing most of the work. Nice job!