Warning: this post will probably be full of overshares, feel free to back out now.
Most mornings I’ll wake up ready for the loo. After a solid night spend sleeping, who isn’t? There have been a couple of early mornings and late nights that I’ve been camping out in the tiny and have had to visit the bushes for a quick wee. Which I don’t really have a problem with, actually (except when the mozzies have just woken up). But I’ve been hanging out for my whizz bang compost toilet pretty much since the get go and it finally felt like I had enough of a bathroom (albeit without a door) to justify the purchase.
As fate would have it, the day I had organised to pick up my toilet happened to be…you guessed, it: World Toilet Day! With friends working in water sanitation and hygiene I often have fascinating conversations about toilets, menstrual hygiene, water usage, etc. and on this fortuitous occasion I was advised to make sure I gave my new friend a nice big SQUEEZE!
Thanks toilet, just for being you!
On a more serious note, having access to clean water and hygienic places to toilet is a big deal and one more thing that most of us take for granted. Today, 2.4 billion people are struggling to stay well, keep their children alive and work their way to a better future – all for the want of a toilet (worldtoiletday.info). Without safe ways to dispose of waste, drinking water often becomes contaminated (if there is any) and there’s usually not enough to spare for washing hands either. Doesn’t it seem silly that a huge portion of the world doesn’t have clean water to drink and we’re busy POOING in ours?? Doesn’t make much sense to me.
Ok, so. Back to the topic. Toilets! More specifically, how do compost toilets work, I hear you ask? Let’s break it down. There are a few different types of compost toilets available, the most practical tiny house option I found is a waterless, self-contained unit with a urine diverter. That means no flush, no water at all. This also means no plumbing and no thinking, for once. Woohoo!
Urine contains high levels of nitrogen (great for most plants) and is in most cases sterile. Why WOULDN’T you put it on your garden? These self contained units direct all the liquids from the toilet bowl towards the front and down into a big pee bottle basically. You can detach the bottle fairly easily, take it outside and dispose of it. This means either tipping it into a normal toilet (although that defeats a lot of the purpose in my opinion. I think sometimes people do this if they’re using the toilets purely for logistically purposes, like if they’re out on a boat), pour it into an existing septic system (these often filter out into a garden somewhere anyway) or dilute it and put it straight on the garden. One part pee to eight parts water is apparently the magic recipe for garden use.
Much like any compost pile in your veggie garden, it seems an important part of the process is to balance out the nitrogen and carbon levels. Before the toilet is used for poo, you put in a base layer of peat moss to ensure there’s plenty of carbon rich material for the composting organisms to consume. This system came with the enzymes to add in to kickstart the process – much like a sourdough starter really! A lot of drop toilets that don’t separate the liquids and solids will require extra carbon to be added in to balance out the wee – hence the handful of sawdust that goes down when you’re done. Not required for these ones.
There also has to be enough oxygen for the grubs to do their job, so a ventilation fan keeps the tank well aerated and also dries out any sneaky liquids that may get in. Rather than a flush, there’s a handle on the side that lets you give the system a crank each time you go, turning everything over and improving the composting process. There are also big patty-pan-esque bowl liners to keep your bowl clean(ish) and to reduce contamination of the liquids with any dangerous poo pathogens. These sit on a little trap door that opens to deliver the goods down into the tank, before closing again to keep out any bad bugs or smells.
According to the manufacturers, the solids tank can hold up to 80 uses before it needs emptying. This will depending on your personal habits and how many people are using the toilet, obviously. This guy (Art Cormier, tiny houser extraordinaire) says he’s had his for 8 months in this video and still hasn’t emptied it! The system breaks everything down even as you use it.
Keeping the two separate also seems to be the key for making sure it doesn’t smell – I can’t testify to this just yet but people swear they don’t smell! Even less than a normal toilet, they say. I’ll report back to you when I’ve got mine fully set up and functional. Once the solids tank is full and needs emptying, you put it out to finish composting in a compost bin in the garden. It’s supposed to sit for another 12 months once it’s out there, to be sure all the harmful pathogens have been cooked off and broken down. Then you basically have dirt, ready to use in the garden! Genius. So simple. And no waste!
The two comparable options I found were the Nature’s Head (shown in the video) and the Airhead toilets. Both come from America and use a very similar design, with a few small differences. After speaking to the pros over at A Better Way to Go in Richmond who stock the toilets and some other tiny house friends, I was sold on the Airhead model.
The ins and outs of the whole set up are explained in far more detail in the Humanure Handbook, an excellent resource and general read for everyone. It’s fascinating stuff, I promise. There are so many taboos topics out there that make it hard for people to talk about important stuff like toilet hygiene. Although I don’t necessarily suggest you start using your own personal toilet habits as an ice breaker in conversations, it’s never too soon to get ready for next World Toilet Day.
Feel free to take my friend Steph’s advice and give yours a little hug too, if the moment is right.