Why does everyone use composting toilets?

[Dem0072]

I've had to live in travel trailers for weeks and months at a time. I can say black water tanks are nasty IMO. Yes, there's little bottles of treatment that can try to take the edge off, there are processes to reduce the headache, flush black first then gray when dumping. And keep the hose sprayed out. But even with vents, toting around 10, or 20 gallons of feces in a liquid tank connected to a hole separated by a thin piece of plastic with a gap, it doesn't take much for the sun to scorch up the asphalt, heat that tank up and all of a sudden you basically have a crock pot of human waste steaming up and creating odor. Some more expensive models may be better ventilated, or more brilliantly plumbed, but the standard theory of how they're installed isn't wonderful. It beats going in a bag in a bucket but not by much.

Composting toilets operate in a different way. Feces is basically 80% water, and only 20% solids. The idea of "sawdust toilets" isn't really composting, it is if you measure the process over months. But not the same way peat moss works. Peat moss has organic microorganisms that basically eat the waste, generate heat, boil off the moisture, and reduce the mass of whats left. The design of the toilet if its decent ventilates the smell out a pipe. The result is something that smells like dirt, maybe with a hint of moss. Decomp takes hours and a day or two, instead of weeks and months. So a single person can make it several weeks without dumping on a Natures Head vs if their black tanks only 15-20 gallons they may not make it more than a couple weeks. With a compost toilet, you can dump your bin into a bag lined bucket and wait till you get to a dumpster. If you're on a black tank only, your whole rig moves to the dump station or you're without a can to use.

The other consideration is, traditional black tanks & RV toilets use water. Every time you flush, you're losing a quart or so of fresh and adding at least a quart or more to the black. That adds up to about a gallon a day per person. So if you're rocking two people, your black tank is done at the end of a 7-10 day stay. If you have kids, or a visitor on top of two people you're basically married to an RV resort or packing up the whole rig to dump every 4-5 days.

And considering a massive 100 gallon fresh water tank isn't all too common on rigs, most people have 45-60 gallon tanks, you're starting to ration showers, people are starting to stink, its not pleasant.

So a composting toilet, coupled with a large fresh tank and a very modest and efficient 1.5gpm shower head goes a long ways to give people an enjoyable stay, hygiene and personal dignity back without being limited to resorts and parks, which lose their value proposition the moment you add up your diesel fuel bill to your resort invoice. I've always believed part of the Skoolie style and experience was about transcending the barriers of traditional RV's, and enjoying the adventure at an economy of scale that you can't achieve by spending $900 for two weeks worth of diesel & park expenses. If you're not showing up to work for a couple weeks or a month, or if your restricted to work you can do from the road - money matters, a lot. Self sufficiency and off grid capabilities become something of a small obsession in order to achieve the lifestyle.

And environmentally speaking, the things peat moss does to human waste are a lot more benevolent than sending it off to a waste treatment center and going all scorched earth with a chemical cocktail.

[Ronnie]

My toilet uses only a cup to flush, less if you hold the flush lever less. We have only emptied our black twice in the last year,and each time it was only half full. Very little oder. It is vented to the outside. If the seal on the toilet is bad or the tank not vented I can see how it could be smelly. A bathroom roof vent is a good idea no matter the toilet.

4 months a year usage for our bus, mostly short trips with a few longer up to a month at a time.

100 gallons of fresh water lasts us 10 days with showers.

[jofred99]

Originally Posted by Dem0072

I've had to live in travel trailers for weeks and months at a time. I can say black water tanks are nasty IMO. Yes, there's little bottles of treatment that can try to take the edge off, there are processes to reduce the headache, flush black first then gray when dumping. And keep the hose sprayed out. But even with vents, toting around 10, or 20 gallons of feces in a liquid tank connected to a hole separated by a thin piece of plastic with a gap, it doesn't take much for the sun to scorch up the asphalt, heat that tank up and all of a sudden you basically have a crock pot of human waste steaming up and creating odor. Some more expensive models may be better ventilated, or more brilliantly plumbed, but the standard theory of how they're installed isn't wonderful. It beats going in a bag in a bucket but not by much.

Composting toilets operate in a different way. Feces is basically 80% water, and only 20% solids. The idea of "sawdust toilets" isn't really composting, it is if you measure the process over months. But not the same way peat moss works. Peat moss has organic microorganisms that basically eat the waste, generate heat, boil off the moisture, and reduce the mass of whats left. The design of the toilet if its decent ventilates the smell out a pipe. The result is something that smells like dirt, maybe with a hint of moss. Decomp takes hours and a day or two, instead of weeks and months. So a single person can make it several weeks without dumping on a Natures Head vs if their black tanks only 15-20 gallons they may not make it more than a couple weeks. With a compost toilet, you can dump your bin into a bag lined bucket and wait till you get to a dumpster. If you're on a black tank only, your whole rig moves to the dump station or you're without a can to use.

The other consideration is, traditional black tanks & RV toilets use water. Every time you flush, you're losing a quart or so of fresh and adding at least a quart or more to the black. That adds up to about a gallon a day per person. So if you're rocking two people, your black tank is done at the end of a 7-10 day stay. If you have kids, or a visitor on top of two people you're basically married to an RV resort or packing up the whole rig to dump every 4-5 days.

And considering a massive 100 gallon fresh water tank isn't all too common on rigs, most people have 45-60 gallon tanks, you're starting to ration showers, people are starting to stink, its not pleasant.

So a composting toilet, coupled with a large fresh tank and a very modest and efficient 1.5gpm shower head goes a long ways to give people an enjoyable stay, hygiene and personal dignity back without being limited to resorts and parks, which lose their value proposition the moment you add up your diesel fuel bill to your resort invoice. I've always believed part of the Skoolie style and experience was about transcending the barriers of traditional RV's, and enjoying the adventure at an economy of scale that you can't achieve by spending $900 for two weeks worth of diesel & park expenses. If you're not showing up to work for a couple weeks or a month, or if your restricted to work you can do from the road - money matters, a lot. Self sufficiency and off grid capabilities become something of a small obsession in order to achieve the lifestyle.

And environmentally speaking, the things peat moss does to human waste are a lot more benevolent than sending it off to a waste treatment center and going all scorched earth with a chemical cocktail.

Do I read you correctly in stating that a Natures Head will "Decomp takes hours and a day or two, instead of weeks and months." ? That sounds like a vendor's glossing over the usefulness of their product.


I've used a bucket system (with peat moss) for about 20 years and can assure you that it even when the pile is kept stirred for aeration, it will take a couple of years before I would like to run my fingers through it.

[ACamper]

Originally Posted by Dem0072

The result is something that smells like dirt, maybe with a hint of moss. Decomp takes hours and a day or two, instead of weeks and months. So a single person can make it several weeks without dumping on a Natures Head vs if their black tanks only 15-20 gallons they may not make it more than a couple weeks. With a compost toilet, you can dump your bin into a bag lined bucket and wait till you get to a dumpster. If you're on a black tank only, your whole rig moves to the dump station or you're without a can to use.

I call complete BS.. I smell a Natures Head marketing agent.

Just sprinkle some peat moss on feces and *magic* it smells like soil and hours later it is decomposed. All you need is a $1000. NH bucket.

[Doktari]

Aerobic decomposition is supposed to be fastest. So the fan is for more than to eliminate odors. And the carbon:nitrogen ratio is supposed to be 10-15:1 (for garden composting piles) which I’ve always had no clue if I was even close in a composting toilet. Then there’s moisture.
I have no firsthand experience with a NH composting toilet so cannot comment directly on that but have lived with a Sunmar composting toilet and bucket system. I’m not sure how long I’ll leave the buckets but probably a couple years.
I can say I’d never do the a composting toilet again if there are other people involved who don’t give a s**t. I’ll compost my waste but I’m not composting other people’s negligence.

[o1marc]

It takes 4 months with proper chemicals, or 6 months to 2 years for human waste to decompose. The name "Compost Toilet" does not infer that it composts in the bucket, but can be mixed with peat moss and put in the compost pile.

https://compostingtoiletsusa.com/how...t-human-waste/

[Dem0072]

Full decomp would take much longer. But having something that goes to work on it considerably faster than sawdust would be a preferred system. The point is, the moss reacting with the waste generates heat, which dries the solids out. Between the microorganisms and the heat based evaporation, you're left with a result that no, you don't want to jump to farming your potatoes in it like Matt Damon. But, you also don't have a log swimming in a tank indefinitely never entering into a process where whats causing bad odor gets eliminated, trying to mask it with chemicals.

People can DIY a composting toilet with the bucket route, nobody has to buy the expensive toilet. But if they had the money to spend, they also don't have to reinvent the wheel on what makes the NaturesHead work decently. And no, I have no relationship with their company, I'm a web designer/developer who enjoys photography. But the consensus of what I've seen a lot of off grid folks doing, the NaturesHead is popular. A toilet is a messy unpleasant apparatus, and it may be intimidating for some to try and think about how they would make one of their own.

[WIbluebird]

Black water tanks are so easy to deal with and there's dump stations just about everywhere. Dunno why people think paying $950 for a composting toilet that requires more work is a good idea.

[cadillackid]

dont regular RV toilets use fresh water to flush? I can see for tyhose who want to boon-dock longer a composting or bucket toilet would make sense as your fresh water would last longer if you are not going to be near a water station for awhile... bags of dry waste stored in sealed plastic tubs and jugs of urine sealed can be kept ..whereas a black tank is usually not huge and would have to be emptied..



for ther weekend warrior who is only out a few days at a time or is at campgrounds 99% of the time then to me an RV toilet or cassette is the way to go..



some here like to stay off-grid for quite a while at a time..
-Christopher

[Ronnie]

about a cup of water for my toilet, and a 50 gallon black tank. Can easy go a month or more on the black tank. Fresh water 10 day supply if taking showers.

[WIbluebird]

RV toilets do use water to flush yes, but they're designed to use very little. If I do number 1 outside when camping then it takes me multiple weeks to fill up my black tank.

[TheHubbardBus]

Originally Posted by DreamWeaverBus

Reasons I will have a homemade composting toilet:

-not gonna waste fresh potable water flushing shite
-not gonna waste space under the bus with a black tank
-not gonna blow 1000 on a factory made composting toilet
-not gonna blow money on a septic system
-from what I know, it's a simpler system, I like that
-great for boondocking
-would enjoy having good compost, great for tomato plants and such

that said, does anyone have any ideas on how to create real compost while traveling? I know it needs to ferment for a while, so you'd have to carry it with you, perhaps a compartment under the bus? In a big plastic tub? Vented of course...
Is it do-able? Difficult sure, but how would you do it?

I was nodding my head up & down until that last line.

PLEASE don't attempt to use human/pet waste ('composted', or otherwise) as fertilizer for edible crops. A composting toilet won't actually compost your feces down to a point where it could be considered compost anyway, but even if it did, composting human waste to a point where it's safe to use for edible crops isn't the same as composting plant matter or kitchen scraps. You'd have to maintain very accurate (& very high) temperatures for extended & measured time periods, assure your rotation method/schedule prevented any of it from avoiding these times/temps, etc.

It's not something most experienced composters consider for good reason, as it takes a lot to get it right, and getting it wrong can have REALLY bad consequences.

What you could do is take the waste from your composting toilet, add it into a pile you maintain with other materials to get the moisture / mix right, and then use it STRICTLY for ornamentals.

[ACamper]

Interesting story on composting toilets, a guy who has been composting human waste for years told me his story of working with it.

Years ago a company sold this small community a “composting out house”. It was the “perfect solution” to human waste. The out house that had 2 toilets and 2 vaults with vault doors big enough for a person to shovel out “compost/soil”.

The instructions were- Use one side until it gets full, then use the other side until it gets full. When the second side gets full the first side will be “compost/soil” shovel it out and toss it in the garden. Easy.. almost *magic* Why would anyone waste money on a septic tank !

What happened- Both sides got full after about a year and a half and when they went to shovel out the “compost/soil” it was still a pile of human feces. Eventually someone had to put on a full bio-hazard suit and spend a lot of hours cleaning up a horrible toxic mess.

The person who took charge of this “composting out house” was crazy, twisted and determined to make it work. So he made a bucket system with 5-gal buckets and straw. Every few days he dumps the buckets and a compost heap after about 2 years of proper composting the heaps are basically usable compost. He uses them on trees, bushes and non-edible stuff. He has done a massive amount of research and work to make it all a realistic and workable system. It takes about 2 years to compost, lots of bleach washing buckets, a good amount of space(away from food prep areas).

I have seen composting feces in action, it does work but it is not what marketing agency's are selling. You can't buy it. It is hard and disgusting work.

[Mountain Gnome]

The Cinderland Eco-community in Puna where I used to live has several above-ground composting toilets that are about 10-12 foot high 3-sided concrete boxes with a door on the 4th side. Jezus, the founder there, told me they fill up every week or two (50 or so people live there at any given time - or at least used to before the volcano erupted). They transfer the compost to the sides of the property, and along the side of the road that leads to the property, and cover it with volcanic cinder. It builds up into 10-foot high mounds that go for sever hundred feet. Then they plant coconut trees, pineapples, and ornamentals in the older piles.


No stink (I've used the toilets), no problems, as far as I know. Maybe because of the weather, as opposed to the above post's story.


Community Guidelines - Cinderland EcoVillage


(it was nice seeing some of the familiar faces of friends I used to know)

[banman]

Originally Posted by TheHubbardBus

SNIP...

It's not something most experienced composters consider for good reason, as it takes a lot to get it right, and getting it wrong can have REALLY bad consequences.

What you could do is take the waste from your composting toilet, add it into a pile you maintain with other materials to get the moisture / mix right, and then use it STRICTLY for ornamentals.

This is because the heat required to render dog/pig/human pOOp! USA safe for your garden is that heating compost that high "sterilizes" the compost making it less nutritious for your garden plants. Heat high enough to kill any potential pathogens also kills all the other organisms needed to grow a healthy soil. You could compare it to a human eating vitamin pills instead of a balanced diet of real, whole, foods.

[gs1949]

I have missed this very interesting thread until today. I am designing and plan to build my own composting system. I have very little experience with composting toilets and have never seen one that was working properly, just one that was not working properly. I won't go into details, but it was very gross.

As others have pointed out previously in this thread, there are not very many real composting toilets out there. As far as I know there are none if you are only including the mass produced drying units commonly sold as composting toilets. If one wants to use an accurate term that is also polite and refined, fecal material dessicator seems much more accurate to me.

Obviously then, I've started this project to design and construct a fecal material composting toilet with no real experience in composting toilets, but what I do have is many years experience at organic gardening and composting. So as I read this thread I don't see much understanding about composting, which doesn't surprise me at all.

Most people simply have not had the opportunity to get into organic gardening and keep their hands dirty for 25 or 30 years. But I have had plenty of composting experience, and I intend to build a system of composting toilets in my bus that will actually produce finished compost. The plural toilets is not a typo, there will be 2.

There are some key points to remember about composting. One key point, areation, has already been mentioned in this thread. Another key point is temperature maintenance. The most important aspect of temperature maintenance is mass. If your pile is not big enough, the only way you will get it to heat is to make it bigger. The same with moisture content. If the material is too dry the good bacteria cannot successfully colonize it, so water will have to be added. But if it gets too wet, the air flow can be restricted and the temperature of the compost reduced too low for the bacterial bloom to get started.

The most common misconceptions I can see about composting in this thread are about how long it takes to produce finished compost that will be safe to use anywhere on non-food crops. I saw one post that said it should take just a few weeks to heat up enough to destroy pathogens, but the general consensus is 2 years. My comment about the 2 years would be that's not composting that's aging, and that's optional. It's really just insurance against people doing it wrong, because most human pathogens won't last 2 years.

I will go with the 3 weeks, but attach a HUGE QUALIFICATION, which is that the ENTIRE MASS of the composting material must be heated. This qualification is much more difficult to attain than it sounds, nearly impossible actually.

In a normal garden compost pile it is only the center of the pile that heats. The outer surface of the pile will only be slightly warm, nowhere near warm enough. So after the center of the mass cools below 120ish degrees F, the pile must be rebuilt, using a manure fork, with the improperly composted material from the exterior of the old pile in the center of the new pile. Normally in a garden situation I would do this 2 to 4 times, depending on what was in the pile and where I was planning to put it. One goal of my compost toilet project is to make a system that will provide adequate aeration and humidity without turning, but I will save that discussion for a more appropriate time.

I apologize for taking over this thread with a long post of my own. I will try to motivate myself to start a thread when I get ready to start building this. But I work alone without a photographer, so taking pictures means I have to stop working.

The link is to the containers I will use for composting chambers. There won't be any 5 gallon buckets used on my toilet project. Five gallons simply won't hold enough mass.

https://www.amazon.com/gp/product/B000LDEP0C/

[o1marc]

Originally Posted by cadillackid

dont regular RV toilets use fresh water to flush? I can see for tyhose who want to boon-dock longer a composting or bucket toilet would make sense as your fresh water would last longer if you are not going to be near a water station for awhile... bags of dry waste stored in sealed plastic tubs and jugs of urine sealed can be kept ..whereas a black tank is usually not huge and would have to be emptied..



for ther weekend warrior who is only out a few days at a time or is at campgrounds 99% of the time then to me an RV toilet or cassette is the way to go..



some here like to stay off-grid for quite a while at a time..
-Christopher

Good post. Reminds me of the TC2000 I bought where the guy hadn't emptied his "bathroom" contents for months. Bottle of 2 gallon apple juice, I guarantee it was not apple juice. Bags and bags and pringles potatoe chip cans filled with crap and toilet paper. This bus smelt like an outhouse and thew guy was living in it.
As I understand it, sphagnum peat moss is the correct medium to use to promote the composting better than other media.

I don't believe anyone that says it only takes one cup of water to properly flush. That's something I would need to see to believe.

[WIbluebird]

On RV toilets the flush handle is foot operated and you simply hold it down until it's flushed to your satisfaction.

[dzl_]

Originally Posted by o1marc

Good post. Reminds me of the TC2000 I bought where the guy hadn't emptied his "bathroom" contents for months. Bottle of 2 gallon apple juice, I guarantee it was not apple juice. Bags and bags and pringles potatoe chip cans filled with crap and toilet paper. This bus smelt like an outhouse and thew guy was living in it.
As I understand it, sphagnum peat moss is the correct medium to use to promote the composting better than other media.

I don't believe anyone that says it only takes one cup of water to properly flush. That's something I would need to see to believe.

Yeah, I highly doubt the accuracy of the 1 cup to flush claim too. Maybe its possible, but I have a suspicion its an overblown marketing claim or myth. If RV toilets truly only used 1 cup per flush, they would be 96% (25x) more efficient than a traditional low flow toilet which uses 1.6 gallons to flush.


This article (no idea if its accurate or a good source) claims "Most use about two quarts of water per flush and have a water-saving rinse setting as well."



This is more inline with what I would have expected (2 quarts = 1/2 Gallon = 8 cups). And if 'most' use about two quarts, some surely use substantially less (1 quart wouldn't surprise me), but I still have a hard time believing that any toilet could reliably use just a cup of water to flush solids.

[Dem0072]

Originally Posted by dzl_

Yeah, I highly doubt the accuracy of the 1 cup to flush claim too. Maybe its possible, but I have a suspicion its an overblown marketing claim or myth. If RV toilets truly only used 1 cup per flush, they would be 96% (25x) more efficient than a traditional low flow toilet which uses 1.6 gallons to flush.


This article (no idea if its accurate or a good source) claims "Most use about two quarts of water per flush and have a water-saving rinse setting as well."



This is more inline with what I would have expected (2 quarts = 1/2 Gallon = 8 cups). And if 'most' use about two quarts, some surely use substantially less (1 quart wouldn't surprise me), but I still have a hard time believing that any toilet could reliably use just a cup of water to flush solids.

To be fair, an RV toilet is just dropping waste into a tank, a straight shot down usually. Which, on a hot day, what goes down can boil and pass its vapor back up which is where my preferences begin to depart with traditional RV toilets. A residential water flush toilet has to push and ensure that toilets waste makes it to the sewage drain pipe on the lowest floor of the house, exiting the house. One's journey ends after a few feet, the other might end up pushing water 20, 30 or more feet. So I don't think in every instance over a gallon would be required. But I do know human waste is messy, and part of what you get with a residential system is a larger bowl and surface area to capture what falls and make it go away. With an RV toilet you're stuck refilling the bowl with water and giving it a rinse scrub with a toilet brush after anything significant.

Both RV systems and composting toilets have the option of ventilation. The expensive name brand composting toilet has that equipped, not all alternatives on either side do. My experience has been with cheaper model travel trailers/RVs, they aren't blessed with benevolent engineering. Maybe $50k would afford the owners $25 in material to make a stink pipe happen.

And the 2 year argument for compost may very well be scientifically accurate. But I think the practical goal is to change the waste enough to get it to not make you pass out when you pull the bucket/bin and to get it to a point where you can just dump it into a bag to be disposed of.

Compost in the organic health conscious gardeners sense isn't really what people are looking to do, unless they're dabbling in earth ships (or farming martian dung potatoes to survive). They just want it to quit stinking, not spread disease or require unnatural chemicals to break down, and they want it gone when they tip it upside down. Pete moss, something to jostle it around, a way to ventilate odors and a collection bin that's separated from the general air supply around the device does that. And it requires zero water, so whatever level of a "flush job" someone defines as acceptable for their preference, it still uses 0.