Composting Toilets USA
Modern composting toilets offer an environmentally friendly and odor-free method of dealing with human waste. There are many models available at different prices, each with advantages and disadvantages.
My first experience with composting toilets goes back about 20 years. After delaying it as long as possible, I had to make a trip to the dreaded outhouse in a Washington State park. However, I immediately noticed there was absolutely no odor. This was unlike every other “outhouse” I had used – where the smell is usually unbearable. A small plaque announced it was a composting toilet – producing natural fertilizer rather than toxic sewage. “Why didn’t someone think of this before?”, I asked myself.
It turns out they had. In Europe, composting toilets have been around for generations. Often called “waterless toilets”, they are installed in homes, offices and government buildings – wherever a toilet is needed. Contrary to a popular misconception, there is no unpleasant smell if a composting toilet is installed properly. North Americans have been much slower to adopt composting toilet technology. However, fresh water is becoming a scarce resource in many areas. It seems wasteful to flush away gallons of pure drinking water every time we use a toilet. In 2005, Americans flushed away 123 billion gallons of water, according to a U.S. Geological Survey report.
Conventional sewage treatment is sometimes impractical or too expensive. Septic systems have many potential problems, not the least of which is disposal of the contents in an environmentally sound manner.
How do composting toilets work?
A true composting toilet produces a safe, non-toxic final product that can be placed on ornamental plants. No expensive or energy intensive treatment is required, and no toxic sludge is produced. Best of all, once the composting toilet is installed, it costs almost nothing to operate.
In a “urine separating” composting toilet, the liquid can be diverted to a gray water system or a small gravel pit (sometimes called a “French drain), where it percolates safely away. Urine is virtually sterile, and does not pose a health risk.
The exact process varies depending on the composting toilet. Generally you have a traditional looking toilet seat and bowl, which sits above a storage tank. This tank may be built-in as part of the composting toilet, or it could be installed below the bathroom in a basement or crawlspace.
Some of the newer composting toilets separate urine from solids.
This is a big step forward. The relative lack of fluids in the storage tank helps eliminate odor. Complete and rapid composting occurs easily. Further dehydration over time allows the solid material to shrink dramatically (just like a compost pile). A small self-contained composting toilet can hold a surprising number of “uses”, meaning you do not have to empty it frequently. Excellent examples of urine separating toilets are the Nature’s Head and Separett.
Most of the older composting toilet designs hold the urine and solids in one tank. Water evaporates with the aid of electric heat, with the same odor free results – at least theoretically. In practice, you must be very, very careful not to introduce more liquid than the unit can evaporate. Peat moss, coconut fiber, biological compost starter or other organic material is often added to the composting toilet to initiate and aid the composting process. In some toilets the solids are rotated, to speed up composting. With some simple home-made composting toilets you just cover fresh material with a layer of sawdust. This requires a LOT of sawdust, generally 1:1 with human waste, meaning you are adding and removing material much more frequently than with modern urine separating designs. It also means you have to store sawdust inside the home – not a great solution.
Ventilation is required with all composting toilets.
Commercially available composting toilets use fans to dry out the contents and prevent odor. These fans are usually very quiet – 30 db to 40 db. (Which is between a whisper and a refrigerator in volume). They usually run all the time, 24/7. The fans pull air from the bathroom area, through the composting toilet and out a pipe to the outside. You never smell anything, even when sitting on the open composting toilet. This is because the fan is pulling air away from you. Any odor is exhausted, and it cannot waft up into the room.
When the solids bin fills up – and this can take between a few weeks and years depending on the type of composting toilet and how many people use it – you empty the already well-composted material into a suitable bin or container so it can “mature”. There should be little or no odor at this stage, other than a slight “earthy” smell. You can read a more detailed article on how to compost human waste here.
How long it must sit is a matter of some debate. It depends on the temperature. Below about 12 degrees Celsius or 55 degrees Fahrenheit composting will slow or stop. Many experts believe letting the compost sit for 12 weeks at room temperature should render pathogens harmless. Others recommend a more cautious 6 months, or even 1 year or longer. It is then safe to use the finished compost on flowers or other non-edible plants. If absolutely necessary, as a last resort, you can bag and seal the solid waste from a composting toilet and and dispose of it in the trash. While this is not illegal anywhere I know of, it is not expressly permitted either. Throwing human waste in the trash is a bit of a gray area. However, I don’t see it as much different from throwing out disposable diapers. I suggest double bagging it in strong plastic bags if you must go this route.
Composting toilets require almost no maintenance and are impossible to plug.
Composting toilets are hygienic, inexpensive in the long run and environmentally benign. As fresh water becomes ever more scarce we are sure to see wide spread acceptance of this technology.
The above discussion attempts to answer the common question: how do composting toilets work? Please also see the pages on how to safely compost human waste, Separett Waterless Toilets, and Nature’s Head Composting Toilets.
Note: Canadian visitors can get important information here: compostingtoiletscanada.
Composting Toilets USA is a division of GreenLatrine Composting Toilets Ltd.
US mailing address:
446 Harrison St
Sumas, WA 98295
Submit your review
I’ve had my Natures Head composting toilet a little over 3 years. It has been nothing but incredible. I have a cabin that I’m in 5 months a year everyday. The toilet is so easy and maintenance free. Absolutely NO ODOR!!! All my family and friends are amazed that it is really odor free. I will be putting one in my RV in the near future for sure. Out with the pain in the butt Cassette toilet.
5+ Stars for sure.
Well, appropriate or not, I really do love this toilet.
I am so excited to have a Nature’s Head composting toilet in my barn studio! It was delivered a couple of weeks ago, and we installed it last week. It’s very easy to use and everyone that’s been over to the studio is fascinated by how it works. But even better, no more trips back to the house in knee deep snow to use the facilities. What a treat!
The toilet is clean and compact, easy to install, and my husband built it into a tidy little enclosure complete with a door sporting a half moon. Very stylish :).
I am also most appreciative of the helpful support from Richard as the toilet was back ordered for a while due to supply chain problems (Covid). He was great about responding to questions about delivery dates and reassuring about shipping.
If you are looking to buy one of these water saving, small space toilets, this is definitely the company to come to. They are great!
I’ve bought two Nature’s Head toilets. They work well. The customer service is superb.
The entire purchase from contact Richard with questions to installation and now 5 months of use has been flawless. We could not be happier with our Separett.
Thank you Richard!
We had already purchased a Nature's Head from the main company and called with questions. Their customer service was friendly but not the help we needed. Richard had all of the right answers and was genuinely helpful. We will be installing a second Nature's Head and will definitely take advantage of his Super Pac deal. Being able to count on his support as we install these in new construction makes us really happy!!
It's hard to get excited about a toilet - what can I say? It works. It doesn't stink. The customer service is exceptional.
This is easy, clean and odor free. Richard spent a long time with me on the phone and made sure it was right for me. No sales job!
I was skeptical. But after 1 year I'm very happy. No odor in our 34 foot power boat. No pump outs!
Richard spent a lot of time on the phone with me, and prevented me buying the wrong toilet (which I was about to do). The toilet has been in operation 6 months now, with no odor.
This toilet does the job, but the fan failed after 2 months. That's why I only give it 4 stars. They did send me two more very quickly however, at no charge.