Thoughts for a non-...
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Thoughts for a non-flush system

New Member
Joined: 4 years ago
Posts: 1
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Hi there,

I’m researching options for a composting toilet system for the tiny house I’m building. I’m wondering it anyone has thoughts on creating a system for a non-flush toilet? The house is on a trailer, so the system needs to be contained within a small space, and I’m trying to minimize (if not nearly eliminate via a purification system) my grey water output.

So far, I have set up space for a drawer under the toilet that can be accessed from outside. The original design was for a composting toilet, but I’d love to try to engineer a vermicompost system. Some possible non-flush issues I can think of that would maybe need solutions: accumulation of material, anaerobic conditions, temperature spikes. 

Many thoughts are much appreciated!



Eminent Member Admin
Joined: 6 years ago
Posts: 37

Hi Mason

Sorry for the delay in getting back to you. The system didn't alert me to your comment and it got lost in all the spam comments.

Yes you can use worms with a non-flush toilet, but this is going to need a fair bit of experimentation to find the best way of doing it and it's not something I've tried so it's hard to advise you. It's also hard to suggest solutions without a clear idea of things like the volume of the drawer under the toilet, how your grey water system is going to work, whether you're thinking of urine diversion and the worms dealing with solids only, or ...?

The huge advantage of flushing (aside from convenience and cleanliness) is that it maintains optimum humidity levels where the worms are situated. Worms need around 60-70% humidity. If you add a means of maintaining humidity, whether water, urine or both, then you also need a drain. The drained water needs to go somewhere. If the vermicomposting system is working as it should be, then you ought to be able to take the output through your grey water purification system (though the worms themselves could also purify grey water), BUT you need to think about what might happen if things go wrong and how you would deal with that.

These vermicomposting systems don't fill up. In fact, you have to add material because the organic material is used by the ecosystem to clean the wastes. In over 20 years of using a single tank, Anna Edey (who's work this concept is based on) hasn't ever had to empty her tank. But there are many variables and much may depend on the ratio of system volume to input.

You need to ensure the temperatures in the tank/drawer stay below 28℃ and preferably above freezing. I don't know where you are, so I don't know how realistic that will be in your climate without insulation.

Anaerobic conditions are only likely to develop if the tank/drawer fills with liquid.



New Member
Joined: 10 months ago
Posts: 2

I am also interested in a non flush system.

Water is a valuable resource here, so I am looking to construct a drop toilet straight into the ibc. Therefor will also have the ability to add a handful of coarse organic material each time to maintain the carbon / nitrogen ratio.

I am able to connect (either or all) kitchen, hand basin, shower and laundry to ibc to maintain humidity levels. 

Has anyone done anything similar or have thoughts regarding this design?

Thanks, Kit.

New Member
Joined: 5 months ago
Posts: 1

I have just begun an experiment with a no-flush vermicomposting system today. This was my purpose for joining this group today, to share the results of my experiment as it progresses.  I will be making videos of my system over time but I'm sort of doing this experiment secretly and don't want to be publicly known for this...yet.. hahah.  To me, this is important engineering. 

The basic idea is:

1) Urine diverting toilet- This could be as a simple as a 5 gallon bucket with a lid on it or a camp toilet seat.  I have a funnel on a riser for male use which empties into a 2 gallon jug.  I'm in the northern US so in the summer I empty every 2 days and use the diluted mixture directly on my garden, or dump it on the compost pile if I don't need it immediately.  In the winter I pack the 5 gallon bucket with sawdust and empty it weekly into my frozen compost pile.

2) Vermicomposted solids- This is the current idea, but it may be adapted- I have a 5 gallon bucket with a snap-on camp toilet seat.  I'm using leaf mulch as my bedding.  I have a trash bag full of leaf mulch next to the bucket.  From my experience, worms do not like sawdust and even after full urine saturation, it doesn't break down very quickly and worms don't seem to be present in it.  My concern with leaf mulch is poor coverage, too low C/N ratio and subsequent smell.  But worms love leaves.  We'll see. 

I have a separate 40-gallon rubbermaid which will be the worm bin. I've put a weed blocker fabric layer on the bottom of the worm bin to keep worms from going out the drain holes on the bottom.  I didn't put air holes on the top sides of the main bin, but have air holes on the lid, and a layer of weed block which will seal out bugs just beneath the lid- and also to prevent a mass exodus of shitty worms in my basement. I will dump my toilet contents every 1-2 weeks, or when it's full.

The worm bin will sit on top of a shallow plastic tote, which is slightly wider than the worm bin. This bin is filled with 3-4 inches of sawdust and wood char.  This is basically the 'greenfield' or the diaper that will absorb any excess liquids that may accumulate and drain. The plan is to minimize urine into this system, only enough to dampen the material.

I'm new to worm farming in general, but I'll probably also add supplementary grit, food scraps, and other bedding materials from time  to time for variation but ideally a person wouldn't need to do this.