This Tiny House stuff just got real. Off grid tiny houses can’t have normal flushable toilets connected to the sewer so other creative alternatives help meet those everyday needs. Composting toilets are that creative alternative.
Composting toilets are toilets that make fertilizer out of human waste. They usually separate liquids from solids to get rid of smells. The solids are mixed with a composting material like peet moss, coconut coir, or sawdust to help them break down. The liquids can be diluted and used as a natural fertilizer.
Compost toilets range from $2000+ down to $10. Which composting toilet is best?
Michelle and I set out on a research journey to figure it out.
I decided to start at the bottom.
I made my own composting toilet (a couple different models actually) to use in our tiny house. They were built completely out of reused materials. I am all about sustainability (reduce, reuse, recycle, and re-purpose), but I also like to save a few bucks too as long as I can make it look nice.
Some of them didn’t work so well, and some worked decent. The first and most important part of a composting toilet is to separate the poo poo and the pee pee. Second, get those solids covered and mixed into some composting material. Sphagnum peet moss and coconut coir work best in our experience. Our other off-grid friends use saw dust and ashes from wood burnings, we took a look (and whiff) of their compost, and there was no bad smell at all. I was quite surprised. We will be testing this out as well soon, and we’ll write up another bathroom blog all about composting.
Anyways, the third rule of composting toilets is: seals, seals, seals.
Smells will try their best to seep out, but if you can seal it and have a vent out, you wont even notice it.
If you decide to build your own compost toilet, I found that putting a seal between the toilet seats was absolutely necessary. We had some extra caulk, so I made a caulk seal on the toilet seat and the toilet seat lid.
Overall, our composting toilets worked pretty well. But unfortunately Michelle was still scared of using them. I cant blame her too much. She’s a super tough girl, but we are all trained to love the comfort of our porcelain thrones. When some of us look down and see a home depot bucket and a funnel, it can be a bit frightening, especially when yesterday’s poop is looking right back at you (see the 2nd rule).
Questions to ask before buying a composting toilet
What is your budget?
Do you want to have the liquids drain out of the house or into a bottle that you have to empty regularly?
Do you have an AC or DC power source nearby?
How much is low maintenance worth to you?
I have done months of research on composting toilets because toilets are a sensitive subject and an important decision (especially to the amazing women in our lives).
I researched so many toilets, knew and talked so much about them, until I became the “toilet guy”.
I didn’t purchase all of them, but I researched the crap out of them.
Toilets worth listing
The best overall composting toilet on the market right now is the Natures Head composting toilet sold for $960 on Amazon. I was very reluctant to get this because of the price. I had a feeling from the beginning that this was going to be the best one out there, but that’s a lot of money for a student (or anybody!) to spend on a toilet. So instead of buying this, I made my own composting toilets for 6 months, but Michelle was still reluctant to use them. After hours more research and testing, I finally decided it was time to buy it.
We got a toilet for Christmas! And there’s nothing I would have liked more.
- It separates the liquids from the solids
- It mixes the poop with the compost material
- It has some decent seals
- Low maintenance. You only have to add compost every 6 months or so. So it also saves you money on compost.
- Fan, vent pipe, and seals keep it from smelling
- Girls sometimes pee into the solids container
- Urine always sits/puddles in between the two drain holes
- Sometimes you might forget to open the solids flap
- The crank handle gets harder to turn
- It is 21″ tall. If you didn’t read earlier, Most normal toilets are about 18″ tall. So this might be nice for those of you over 6 feet tall with long legs. I’m 5’10” with long legs, and 21″ toilets are uncomfortable for me. My feet don’t sit nicely on the ground, and my legs start to fall asleep after a while.. So I use a squatty potty 😉
There are two different crank handle options – the spider handle and the standard handle. Michelle and I prefer the spider handle because it doesn’t stick out as much as the standard, and we can turn it with our feet. This is nice because we don’t like to be on the bathroom floor any more than necessary.
The price is high, but it is worth it compared to the others.
At $1,740 this composting toilet is nice because it doesn’t use electricity, but you need to have somewhere for the 4″ vent pipe to vent out of your bathroom.
You also need a drain installed in the bathroom for the urine. It does not collect in a container inside. This means less maintenance, but you need a drain.
It’s a good toilet, but overpriced for what you get.
This one is harder to find. It costs $250ish plus shipping.
It is essentially a Home Depot bucket with a toilet seat on top and a urine funnel inside.
The solids go into a compostable bag in the bucket while the liquids go through a small funnel (don’t miss) and into a holding tank located behind the toilet that must be emptied.
This is a Super simple toilet that doesn’t mix the compost. It costs about $300 with shipping, but you could make it for under $50 or so. If cheap, simple, and normal maintenance is what you want, but you don’t want to build your own, then this could be a decent option.
Separett has 2 models, an $889 version and a $1349 version (plus shipping).
The $889 version – the Weekender 7000
Don’t ask why they though the 7000 part was necessary, it sounds more like a luxury car than a toilet to me.
- Separates the liquids from the solids
- Has a fan and vent pipe (no smell)
- It has no moving parts, so it is very minimal, but nothing great in my opinion. Definitely not worth that outrageous price.
You have to purchase compostable plastic bags. This is basically the same concept as the first compost toilet I made. We put a bag in a bucket with a toilet seat on top. You have to add some compost on top of your poop every time you use it. But it doesn’t compost well because you have to replace the bag at least once a week. Compostable bags sound cool, and they do decompose but it takes quite a while, and you get pieces of bag mixed in with your compost.
It’s a little tall. 21″ Most normal toilets are about 18″ tall. So this might be nice for those of you over 6 feet tall with long legs. I’m 5’10” with long legs, and 21″ toilets are uncomfortable for me. My feet don’t sit nicely on the ground, and my legs start to fall asleep after a while.. So I use a squatty potty 😉
The urine drains out of this toilet, it does not collect inside. So keep in mind you need a drain pipe for it to leave your bathroom.
Click here for more info on the Separett.
The $1349 version – The Villa 9200 has some neat features, but costs more than I can pay for it.
Its coolest feature is that the poop hole trap door automatically opens with the weight of your body when you sit down.
It rotates the solids bucket like a microwave rotating plate to “evenly distribute” the solids. But it does not mix the solids with the compost. You have to add compost on top each time you go #2.
The Separett requires you to buy composting material and compostable bags on a regular basis.
There is no urine collection tank in this toilet either. You need a way for the urine to leave drain out of your bathroom.
Click here for more info.