If you are planning to build a tiny house, you will need to make a decision about the toilet. Does the idea of scurrying to an external restroom in the cold and dark bother you? Not interested in emptying a chamber pot? Many tiny houses are designed to have an internal toilet for these reasons. Your two choices are a composting toilet or a flush toilet.
Depending on how often the tiny house is moved, where it is located and how cold it gets, indoor plumbing can be problematic. You may be required to establish a septic tank or connect to a sewage system. If you are motivated to solve these problems and get a flush toilet operational, go for it. But first, find out the advantages of a composting toilet.
Many tiny home owners opt for a composting toilet. Some advantages are:
- They generate compost, reducing waste
- They use less water than flush toilets
- Fits any budget: from home-made to $150 basic toilets to $1000+ external tank systems
- They are easier to set up than plumbing
- No dependence on “the grid” such as municipal plumbing and sewage systems
- Some require electricity and/or a battery, but many do not
Composting toilets are notable because they use little or no water. Typically, inexpensive sawdust is sprinkled into the toilet after each use. Coconut coir or peat moss can also be used. No flushing is needed. The sawdust introduces air and blocks odors.
The toilet may look similar to a regular flush toilet, or it can be a home-made design. In a self-contained type, a tank system is set underneath the seat and sometimes under the floor. This is where the waste gets broken down. A small fan may be used to evaporate excess moisture. In some cases, a separate system may be set up for liquid waste, to reduce excess moisture in the composting toilet.
Fancier composting toilets suck waste and a small amount of water into a tank system. These are more common for larger houses that have more than one toilet; tiny houses will only have one toilet. Some tiny home owners may opt for this type of system if they want the waste flushed into a tank under or beside their abode.
A typical composting toilet uses an aerobic process, using air, bacteria and a filler (sawdust) to let the waste naturally decompose. A fan may be used in the toilet to introduce air and reduce moisture. Latrines and outhouses, on the other hand, are anaerobic and therefore, highly malodorous.
Composting worms are often used to speed up the decomposition process dramatically and reduce odors. Here at Uncle Jim’s Worm Farm, we often receive orders for Red Composting Worms that go into composting toilets. These red worms are champion composting worms that we have cultivated over the past 25+ years. They quickly gobble up organic matter and break it down. Composting with worms is called “vermicomposting.”
Odors are a primary concern in a tiny house. Adding coffee grounds helps mask any odors. Fine sawdust does a better job of masking odors than big chunks of sawdust, and you can get them from lumber yards for free. Specifically, pine shavings smell great and last a long time. When needed, use a natural technique to keep the air smelling fresh in the bathroom, such as opening a window, running an exhaust fan or lighting some incense.
Most composting toilets are designed to let the broken-down waste collect in a separate part of the toilet or in a tank. As time passes and the toilet gets used, the waste is gradually pushed into a place where it can be removed through a separate access port.
Once in a while, the composted material needs to be removed. It should be around 1/10th of the original volume by the time the process is complete. And it should be dry and odorless. The composted material gets scooped out, typically from another port. However, since this is human waste, check your local and state regulations. You could unintentionally spread disease or harm your plants if you put it right on your vegetable garden or mishandle it. Some states only allow this compost to be used on ornamental plants at a minimum 12” depth. In some places, the compost has to be buried away from plants.
A well-maintained composting toilet is perfect for tiny houses. It can be operated off-the-grid very inexpensively, and uses little or no water. Be sure to consider a composting toilet when designing your new tiny home. Also, order composting worms from Uncle Jim’s Worm Farm to speed up the process.
8 comments on “Tiny Houses Adopt Composting Toilets with Worms”
I’m seeing all over the use of worms for decomposing. Never thought about for the sewers, but of course, that is so environmentally friendly, cool to see some people moving towards that future.
Fantastic concept, as with most people the smell would be a concern. But I like the idea of coffee grounds and/or pine sawdust being used to control smell. 1/10 the volume after the process is complete is pretty awesome.
I’m glad to know that I can use worms in my composting toilet because I find that it needs help to break down. It really doesn’t have a smell if you use either the saw dust or the recommended composting material. I’m looking forward to trying it. If I ever get a new one which will be any time soon, I would get the one that has the urine separate because depending on how often you pee your tray could overflow even with the air flowing to dry it up. Don’t get me wrong the material does soak up most of it. I hope I’m not offending anyone. Just FYI.
What I’m interested in knowing is how many worms to start with even if babies and what to do when you get a lot of worms in your composting toilet because they are multiplying.
What I would like to know is if an established ‘colony’ of worms could be used in a traveling tiny home. In an established place, no problem. But does the road vibration irritate the worms enough so they would try to escape? Has anyone tried this?
The general rule of thumb is one-half pound of red worms in an opaque (not clear) 12×16″ tote (192 square inches) for the food waste of one or two people. Maybe that would apply for poop, too. (There’s not a lot of info out there about this!) Also, surface area is more important than depth. No container needs to be more than 12″ deep, as these worms are generally surface worms. A good book for using composting works is “Recycle with earthworms : the red wiggler connection” by Shelley Grossman. It’s about feeding them kitchen waste, but the same rules should apply, I would think.
How does this process work in the winter? When the ground freezes? Does the composting bin need to be a certain temperature?
I’m a bit confused about winter composting (like if, or how often I can add to the pile?). I think worms do not like temps below 55-degrees Fahrenheit. They stop eating and become sluggish. I don’t know if they can survive freezing. I’d bet not. It is possible to insulate an outdoor compost heap with a few-to-several feet of leaves and/or mulch; covered by a tarp. Also read that cooked rice tossed in will give off warmth as it decomposes, helping the worms survive winter.