Composting Toilet

Flush toilets (and the mega sewer systems that go with them) waste a lot of water and destroy ecosystems. Septic tanks are mini versions of the municipal mess makers. Besides, why would you want to flush something away that can help you build great topsoil and grow tasty vegetables?

Becky and I both read The Humanure Handbook by Joseph C. Jenkins. (This is the authoritative text on composting human waste.) We decided to go with the bucket based model described in the book because it was simple, effective and inexpensive. I’d actually built and used one of these for a couple of years back in the U.S. and found it to be a great system. We used scavenged wood for the base and legs. Becky’s cousin, Paul, happened to have an unused, deluxe wood and brass toilet seat in his garage. The most expensive bits were the buckets at NZ$6 each.

Bucket throne

We decided to put the toilet in the garage (which we use as a storage area and workshop) because it features a short and clear path to the outside. We didn’t want to have to carry our crap too far and we wanted to minimise the risk of catastrophic spillage mishaps. Becky put a curtain around it for privacy.

We’re happy to report that the bucket is filling up nicely. (And it doesn’t smell!!!)

13 Responses to “Composting Toilet”

  1. willy_macoy says:

    Great work, Kevin. Now, what are you going to do about the toilet paper? 10c or more every time you go for a dump. Plus the environmental damage of bleaching paper that is going to end up in a compost bin.

  2. Kevin says:

    We’re going to plant some Brachyglottis repanda, common name: Bushman’s Toilet Paper. Big, soft, furry leaves.

  3. zaneparker says:

    We started a humanure system on our property about a year ago, and I am happy to report that it is working great. We haven’y yet harvested any of the proceeds, but we have filled up two piles now (a bit more than the handbook projects). I find it very strange now when I have to use a “real” toilet and flush my “waste” away. I wanted to point out that the handbook is fully available online too, at:

    I envy your hemispherical situation right now…


  4. tochigi says:

    Composting toilets…a subject close to my heart.
    a few years ago we stayed in a really cool place called the San Souci Inn, in Pohara near Takaka, Golden Bay.The couple from Switzerland who built and run it have used a cool system with a slope and fan for odorless efficient composting. If you are interested in the design, maybe write to them…

  5. Kevin says:

    Oh yeah, if you put some money and effort into engineering a composting toilet, the result is truly a thing of beauty. Becky took me on a hike out to a place called Lane Cove. I’d certainly never seen anything like this in my life. Have you ever played the game Myst? It reminded me of that, except it was pinch-yourself-real! Wait, was it a holodeck? Naaa. It was real.

    I would make it one of your missions in life to get there. It’s probably not very well known, but there’s a hut right on the beach that can be rented. There’s a gravity water system and an incredible composting toilet! (No power. HA)

    Check it out and shhhhhh! don’t spread the word around too much:

  6. tochigi says:

    whoa! looks like i’ll be heading up north next time i’m in nz! that looks f-ing unbelievable.

    thanks for the tip. i’ll keep it under my hat 😉


  7. willy_macoy says:

    Back to the toilet paper thing, Kevin, I have a friend who uses water alone. No paper, no leaves. Swears by it.

  8. Jessie says:

    Wow, this is awesome! I have to get my hubby make one too. 🙂

    @willy_macoy: Uh, how does he do that??

  9. Rebecca says:

    Just been reading with interest your entries about composting toilets. We have recently bought about 3500 square metres of rugged land on the Catlins Coast which we are developing as a back to basics kind of place for us to stay over the summer months. We have found heaps about people’s experiences with bought composting toilets but little about DIY type ones like yours, which is what we are trying to do. I would love to hear how the composting toilet is going and any advice you could give us for ours.

  10. Kevin says:


    Any possible questions that you have, and hundreds more that you haven’t even thought of yet, are answered in the Humanure Handbook referenced in the post. Here’s a free version of the book if you don’t want to order it or can’t otherwise find it:

    I can’t recommend that book highly enough. That’s how we learned.

    The bucket/cartage system works very well. If you’re only going to use it for a few months at a time, the bucket system is the way to go. For long term use, while the bucket system works fine, I would suggest building a dedicated system that doesn’t involve cartage.

  11. Deirdre Kent says:

    Hi Kevin

    We have just read the book on Humanure too. Dave Johnson the local EM guy said if you make your own bokashi and use this instead of straight sawdust, you can put the proceeds into a barrel and squish it down (will have to find some mechanism) then it would only take a month to be usable. So today we made our own bokashi. Four parts of sawdust, one of bran and then a 2% EM mix. So it is sitting waiting for the first call of nature. We haven’t got our seat arrangement yet, but have two stainless steel buckets from Mitre Ten. We will have one bucket for urine and one for faeces. I must say we have just had two sets of visitors and when they were around, we didn’t show them the buckets at the ready. Funny how even with family members sometimes you don’t feel the energy to get into that discussion…

  12. cam says:

    Very interesting!