Composting Toilets Made From Wheelie Bins

I just read a post on composting toilets here on the PRI site and remembered that I never posted about the composting toilets I made last year (for various projects) based on a similar principles, but a distinct design. Below I offer a few words of introduction and then post photos of the building process with instructions.

As part of various projects that I’ve helped organise over the last six months, I self-appointed myself the maker of composting toilets. Some people might have been happy to delegate such a job to others, but I wasn’t that generous to my collaborators. I wanted the job for myself, and in this post I briefly describe the process with pictures and a few notes.

Before getting to the building process, let me tell you why I find composting toilets interesting and important. First of all, in a world where two and half billion people still lack regular access to clean drinking water, defecating into drinking quality water strikes me as the height of insanity. Obviously, most of us have no existing alternative. But that doesn’t change the insanity of our current system. Composting toilets provide an alternative. Not only do they avoid the need to defecate into drinking quality water, they require almost no water at all.

The second reason composting toilets are important relates to energy. Existing sewerage systems require a huge amount of energy to create and operate; composting toilets require very little energy, and can even be made from recycled materials (as I did, for the most part). Furthermore, most fertilisers require fossil energy to be produced. But not home made compost; it is fertiliser.

The overconsumption of fossil energy lies at the heart of the some of the world’s greatest problems at the moment, so we clearly have an incentive to reduce energy consumption wherever possible. Rather than importing energy intensive fertilisers and creating energy intensive infrastructure, why not compost the organic matter we produce through our digestive system every day?

At this stage some people will be wondering about the safety of composting toilets, especially using the compost (or ‘humanure’) as a fertiliser. I will not summarise the science now, but instead refer you to the master, for there is no better source than the Humanure Handbook, by Joseph Jenkins. Read this before creating your own system. For decades Jenkins has been rigorously studying composting toilet systems, and his scientific experience shows that, when they are done properly, composting toilets are safe. The biological processes that take place when composting human waste kills harmful pathogens, making the end product safe for use as a fertiliser. This biological process can be complete in as little as three months, but to be safe, I’d let it sit for a year.

I would not recommend using the compost near or on vegetable gardens (although, to be clear, when it has composted properly it is safe to do so). But humanure is ideal for fruit or nut trees or for non-edibles. Of course, it is important to take care when dealing with human waste, so do your own research and check regulations before you begin. But just as there are some (limited) risks to composting human waste, there are also risks to not composting (such as causing climate change through superfluous energy consumption!). We need to rethink our relationship to energy (and water) consumption, and composting toilets provide one aspect of our lives that deserves attention.

As I was researching this subject, a friend told me about an old Chinese custom related to composting toilets. Apparently, if you were invited to someone’s house for dinner, it was considered rude not to use their toilet before you left. The reasoning behind this seemingly strange custom was that, if someone is good enough to feed you, the least you could do is leave them the surplus nutrients via their composting toilet system. Interesting how times have changed. The past has much to teach us, especially if infused wisely with the present.

The following method includes a tap to allow liquids to be drained, and a ‘false bottom’ to keep the solids above the tap line. Take care with the liquids however as they’ll likely have traces of faecal matter. One option is to dig a hole 400mm deep, drain when necessary, and cover with earth or mulch. The solid waste (poo) in the bin won’t compost if it is sitting in liquids (pee), although it does need some moisture to support the biological processes. This system composts human waste by mixing it with so-called ‘brown matter’ or ‘carbon’, like straw, dry leaves, or paper, which must be added by the handful each time the loo is used. If the loo ever stinks – it won’t stink if it’s working properly, but if it does – this tends to mean you either need to add more carbon or drain the liquids.

Basic Materials:

  • 1 second-hand wheelie bin
  • One tap
  • Drill with appropriate pieces
  • 1 used bread crate
  • Several screws
  • Some ag pipe
  • Plywood
  • Wire mesh or shade cloth (I used mosquito netting from the salvage yard)
  • Recycled wood
  • Toilet seat


Begin with a wheelie bin


First thing to do is drill a hole about 10cm from the base, at the front


To do so, I used the drill piece shown here


You want to make the hole the right size for your tap, so that the tap can be wound in snugly.

You will see in the picture of the tap that I haven’t wound it all the way in. Leave a little room for silicon. When the silicon is dry, wind it in properly, and to be safe, do another round of silicon. I was advised to do this by the guy at the hardware store, but aren’t sure if it was necessary.


You may also want to ensure that only liquids ever get into the tap, so I took the precaution of
adding a mesh to the inside. You also want to silicon that too (same way as with the tap).


Now you need to add a false bottom to the wheelie bin by cutting out the appropriate size.
I used a bread crate, which I picked up from the tip shop.


You need to cut it to size with a hacksaw or jigsaw.
Fortunately I had a template provided by a friend.


Once you’ve cut it to size, wrap some mostiquo netting or shade cloth over it and attach it
with small bits of wire.


You then need to attach some wood to the sides of this to keep it off the bottom of the bin


Then place it in the bottom of the bin


You then want to add an air hole at the top. I used the thing above, but you could just cut a
hole and attach shade cloth over the top. It needs to have a mesh, otherwise flies will get in.
This allows you to attach piping to create an air vent if used in enclosed spaces
(you can even put a little fan in the piping to suck air out of the toilet through a pipe).



Cut a tight-fitting hole and silicon it in.


You now need to bolt some ag pipe (pipe with holes in it) to the back corner of the bin.
This allows air to get to the bottom of the bin, even as it gets full.


Now for the top. Get some thick plywood 18mm+ and cut a square that covers the whole bin.
Place the toilet seat in the appropriate position and trace the inside of the toilet seat. Cut out.


Screw plywood to bin, then bolt in toilet seat to plywood with the bolts that come with a toilet
seat. You will also see that I’ve added a screw to the front of the toilet set to keep it sitting flat.
(Depending on the type of toilet seat you use, there may be a gap at the back of the lid that
you’ll need to fill in order to keep flies out. You could use some of the off-cuts of the
plywood for example.)


And you’re done. Fit for the Queen’s bottom.


I made four 240l toilets and two 120l versions

A similar wheelie bin system to this was used in Christchurch, New Zealand, after the earthquakes, and is also used by the fine folks at Milkwood Permaculture too.

For other examples of alternative technology that I’ve written about, see my posts on solar ovens, my post-electric washing machine, and my non-electric fridge.

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38 thoughts on “Composting Toilets Made From Wheelie Bins

  1. Thank you so much for this detailed guild! I desperately want to do a set up like this for my family, but I am curious about using these in a home type setting especially where winters are cold. Has anyone seen the wheelie bin composer used like that or have any suggestions on in home toilet?

    1. Yes it all works fine, right out to extreme cold climate, the inactive frozen material thaws in Spring time and goes through a rapid decomposition process, with the more diverse and active micro-organisms of those climates.

    1. You let it sit for a year, then use it. While one is sitting, you use a different one. You may need two or three (or more) depending on how many people are using it. As for excess liquids, the first thing is that you shouldn’t need to drain excess liquids if most people don’t pee in it. Pee behind a tree (or on the lemon tree!). The wheelie bin system does need some moisture to compost properly however. But it won’t compost if sitting in liquid. So drainage can be required. Dig a hole (say, half a metre) when necessary, drain liquids, then cover with earth. Again, there is lots of information about the science of humanure online. I’d recommend everyone does their own research before setting up own system, starting with the Humanure Handbook.

    1. I think the usual way of doing this is to build a wood-framed latrine with a roof, walls and a door, and with steps going up to the door. The wheelie bin can be rolled into the small building from the rear. Here’s an example.

  2. Awesome. We need more of these everywhere. Thanks for the detailed guide :-) Do you by any chance have a PDF version of this?

  3. @Guillermo Moreno : If you want a PDF, then look for “Joseph Jenkins” in the text on this webpage. It will lead you to a hyperlink which points to the Humanure Handbook. You can freely download the older versions, or buy the newest ebook, or read it online. Or take a look at http://www.toiletrevolution.com/ , about the toilet revolution taking place in the UK and Ireland.

  4. Totally uncomfortable, that´s the only flaw I see in your designs. I promise I couldn´t shit there because my legs would hang or be in weird positions. Look at a conventional bowl to understand what I´m saying.

    1. They are at normal height usually Dan of course, and inside a toilet building for obvious reasons of privacy, and of course apart from NOT using 30 to 40 thousand litres of water per person per year, you cannot tell them apart from the toilets that have become NORMAL, with their extreme water consumption.

      1. I can see where Dan’s coming from Geoff. Mounting the toilet seat directly over a flat piece of wood cannot be as ergonomic as the modern “bowl”. I can envision one or two splinters in some rather uncomfortable spots.

        However, the design aspect of the toilet seat (or indeed the entire throne room) has little to do with the functionality of the ‘receptacle’ (bin) below. I don’t see why anyone couldn’t create a ‘modern toilet’ design by mounting (an appropriately shaped) ‘bowl’ over the floor cavity. You could even use the standard cistern as a storage point for dry material and a really smart person could adapt a ‘flush’ mechanism for it too… so many possibilities.

  5. Compost toilet heaven is about to arrive here on your favourite website. Because of the incredible lack of understanding of compost toilets and because Zaytuna Farm is in Northern New South Wales, Australia the most advanced place on this earth when comes to compost toilets and reed bed grey water systems and where they are the PREFERRED system of use for rural dwellings by the local government. I decided to send one of our office staff heroes Ingrid Pullen ( photo journalist extraordinaire ) out on an adventurous mission we have named the “Poo Shoot”. As it happens our associate town planner the amazing Rob Doolan has just achieved a local government approval for wheelie bin toilets to cater for 30,000 people, they have been installed, and are fully operational and filled to capacity with a complete success, working perfectly.
    So hang in there and we are going show how to get your shit together BIG TIME.
    I have also just documented a methane gas digester built at our PRI Master Plan Site at http://permaculturesunshinecoast.org which will soon be released as a free short film and again we are going to keep showing you many ways to get your shit together.

    1. How would LIsmore go with a composting toilets in a low impact sustainable urban development right in the CBD of Lismore – 5 storey

  6. Solid gold diamond studded compost toilet worth $1,000,000 compost toilet any seen more expensive, NO NO NO (comedy break) just joking folks.

  7. Hamish Skermer, of Natural Events, supplied nearly a thousand similar to these at Glastonbury Festival this year. vs only 150 plastic portaloos, which are being phased out. I think his system uses lots of worms for the composting.

  8. We used to have composting outdoors toilet in our summer house when I was a kid. Used to decorate the walls of the ‘outhouse’ with quotes and pics from magazines. Had sawdust and ash to drop on ‘deposits’ after. Never had any smells. Good old days!

  9. Can you use worms to compost it? I’ve heard mixed things about using worms to compost poo by anything that eats meat. In other words I was told not to use worms to compost cat or human poop. I’ll have to get the Humanure book. I will be the first to admit that 2 years ago when I heard about that book and about composting toilets that I was totally grossed out. But not any more. Wish we could have them at all the festivals in towns instead of port-a-pottys. I used a compost toilet at a convergence and it was 100 times better than the port-a-potty!

  10. A urine diverting seat would reduce odor, and keep the solid material only slightly moist (perfect for composting). The urine could drain to a second tank. Now, because the urine has NOT come in contact with poop, it is sterile, and can be drained into a small pit or anywhere – safely. The liquid draining from the bottom of this wheely bin design will be contaminated and a considerable health risk. A small, but extremely important improvement. Otherwise, good design.

  11. Wheelie bins – your council may have ones with detached lids etc they can give you. Cutting up the bakers tray – easy with an angle grinder – can get a perfect fit. Can also support it with plastic flower pots – surprisingly strong. And greenhouse shading is very cheap and easier to find that fly screen. A hot glue gun fixes everything securely in place and ensures a gap free fit. And instead of a tap, try a cheap and simple radiator drain fitting – a hose pipe will fit straight on, and it can be turned on and off with a small spanner or even pliers.

  12. question – how to improve air circulation through the contents. I can see you’ve got the ag pipe close to the vent (my vent goes directly up from the seat platform in a continuous stright line through the roof to remove the bend). But looking at the Biolan purpose built ‘wheelie bin toilet’, this has a patented device. Could circulation be improved, e.g. by allowing air to enter underneath the mesh, but above the tap level of course.but without connecting that small void to the vent pipe, the risk is that the air will flow the wrong way and cause smells. Anyone done any experiments with this, or taken temperature readings with and without improved air flow? One simple thing – having a shorter, and wider diameter liquid pipe, and leaving the end exposed to the air instead of underneath the fluid level in the container…

  13. how about hot gluing or wiring the end of the ag pipe to the bread tray/mesh, and then inserting the ag pipe loosely into the bottom of the vent pipe, to get a little negative pressure flowing through the heap? Or making a good seal for the toilet seat so the draught up the vent is pulling through the compost?

  14. I know someone with a toilet like this in Nimbin, but it’s a bit different. They have built an open air toilet on the second storey (with a view), and the wheelie bin is on the ground floor.

  15. Why is the tap placed so high? surely the tap should be as low as possible to be able to drain all accumulated fluids?

  16. Firstly, thank you so much the detailed information and photographs….even an illiterate in this field could follow them.
    However, big question here: assume you are in the sub-tropics and have full wheelie bin….how long would it take to become inert after the liquid is drained off?

  17. Nobody has mentioned that adding a urine diverting toilet to the top eliminates having to put a tap on the bottom . It also eliminates possible odour problems . I recommend adding biochar to the sawdust . This also then ends up making a much better end product for the garden. ( find out how to make own biochar). A cheap urine diverting toilet needs to be sourced ! Can anyone help? Peter

  18. Re previous comment ,I recommend that diverted urine is fed into plastic container with tap half filled with water . This fluid can then be very safely used on garden. Peter

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