Composting Toilet Types: Remote and Self-Contained Units Compared

Recently, more and more people have become interested in installing a compost toilet in their home. Compost toilets have many environmental and financial advantages: they help conserve water, they help reduce the possibility of sewage or groundwater pollution, they eliminate the costs associated with maintaining sewers and septic systems, and their end product is actually beneficial for the environment (compost) instead of polluting.

However, if you are shopping for a composting toilet, you may be a bit confused by the selection and the different models currently available. There are literally dozens of compost toilet manufacturers offering a variety of different types and features on composting toilets to choose from. However, there are two basic different types of composting toilets that you must choose between: self-contained or split (also known as “remote”).

Self-contained compost toilets are ideal for small homes and spaces. They are quite easy to install and are often ready to go right out of the box. There are both electric and non-electric versions that you can purchase. Electric versions usually have a fan that helps maintain the correct moisture density within the composting chamber. They also tend to be cheaper than the split composting toilet models.

Some of the down-sides of self-contained models include the small number of individuals they can adequately serve – most models cannot handle more than two people, and some may only be suitable for one individual to use on a daily basis. They may also appear a bit bulky, and many models are quite tall and require a foot stool for use. Some consumers find them more difficult to maintain as well, since the smaller size requires more frequent monitoring to make sure the compost stays in balance.

Split, or remote, composting toilets are the best choice if you will be having multiple individuals using the toilet on a daily basis. With a spit model, the composting chamber will be located in a different part of the house (usually directly beneath the toilet in a basement area) and many models look very similar to a regular flush toilet.

Split compost toilets generally are more expensive than self-contained models and require additional installation and plumbing costs. You also need adequate space and an appropriate space to install these units in your house. However, when you factor in the savings you will have in water costs and sewage or septic system maintenance costs, these units should still be a good economical choice.

In sum, by taking into careful consideration the number of people who will be using the composting toilet and the space available in your house, you should be able to find a composting toilet that works well for you and is the right choice for the environment as well. Just watch this clip of a National Geographic special about composting toilets to learn more about the importance of composting toilets to our environment and the world.

Bill Boor has written numerous articles about composting toilet systems and portable composting toilets.

Outdoor Portable Composting Toilet Systems

Composting toilets provide an important solution to the issue of dealing wit human waste.  New home composting toilets on the market are able to recycle human waste into the environment quickly and with little odor.  But the home models are quite large and what if you are on the move? What if you need portable composting toilet for an outdoor event, a boat, recreational vehicle or your next camping trip?

Fortunately there are now new portable composting toilet models being manufactured that are ideal for campers, boaters and RVs.  And if you aren’t interested in purchasing a ready-made composting toilet for your next outing, there is also the option to build a cheap portable composting toilet at your final destination in a matter of a few hours.

Manufactured Portable Composting Toilets

There are now several models of portable composting toilets on the market:

Camping Composting Toilets

ne of the main reasons to purchase a portable camping toilet is to take care of the environment you will camping in, and you can take this step even further by using composting or environmental camping toilets. These models will avoid using any chemicals in their processing of waste, and will instead rely on composting and similar processes to dispose of waste in an environmentally responsible manner.

For those who love spending time outdoors, taking time to care for the environment should be of the upmost importance. Portable composting toilets can help manage and dispose waste without using chemicals, thus protecting the environment.

One of the most popular models is the the PETT Environmental Toilet. This portable composting toilet can be used by individuals up to an amazing 500 pound weight limit. When folded, however, it is about the size of a small briefcase. It is light-weight, about seven pounds, and is a popular unit used by the Forest and Park Service as well as FEMA. The PETT toilet uses an environmentally safe powder to help gel liquids, remove odor and promote decay inside the unit’s biodegradable bags.

Another very good option is the BoiToi portable camping toilet. The Boi-Toi also uses 100% compostable and biodegradable bio-bags to dispose of waste. The model is used globally by NATO forces.

Each of the Bio Bags will decompose within 40 days when composted properly. This means it one of the most environmentally friendly portable camping toilet models available. It is also very lightweight (4.4 lbs) and affordable as well, costing under $50.


Click Here For More Environmental Portable Camping Toilet Options!

Large Portable Composting Toilets


If you are looking for a portable composting toilet similar to the portable toilets you see at fairs and other outdoor events, or your recreational vehicle or boat, there are several decent ones available on the market. Nature’s Head has a small self-contained composting toilet that is quite popular with boaters. You will need no chemicals to maintain this composting toilet. The only thing you will need to add is peat moss to keep the composting mixture balanced in terms of green and brown organic matter.


The Sun-Mar Self-Contained Composting Toilet is another excellent choice in terms of medium sized portable composting toilet (although also a bit pricey – it costs around $1800 U.S.).

Building a Composting Toilet on Site

Finally, if you are interested in an even cheaper option for a composting toilet outdoors, you can try building a composting toilet toilet on site cheaply using five gallon composting containers.  If you are interested in learning how to build your own composting toilet, you can read the instructions here.

For even more information about composting toilets, including articles on How Toilet Composting Works and the Environemental Benefits of Composting Toilets, please return to the Toilet Composting Home Page.

Composting Toilet Systems: What You Need to Know

There are many different kinds of composting toilet systems currently available for home consumers to purchase. Composting toilet systems generally contain the following four components:

  1. a reactor, which is the container in which the composting takes place;
  2. an exhaust system, to remove odors and help control liquid build up;
  3. a means by which to turn the compost (for some systems, some will not need turning);
  4. a way to remove the finished compost, which may be as simple as an access door to the finished product

How these four features are integrated into the composting system vary considerably, as there are many different composting toilet models that have been developed by composting toilet manufacturers. With most composting toilet systems the entire composting process will take between six to twelve months of time, after which you will be able to remove the finish compost and use it as a soil amendment for trees, flowers and other non-agricultural uses.

When evaluating composting toilet systems, it is important to know that there are two important different ways in which these systems can be installed in your home.

First, there are self-contained composting toilets. With a self-contained unit, the composting process takes places in a reactor directly under the toilet seat. These composting toilets are often quite high and large, and may need a small footstool for use.

Next there are remote composting toilets (also called “split” or “centralized”). With these systems, the reactor is located in another area of the house, often in a basement. The advantage of remote composting toilet systems is that the toilets look and are used in a manner which is quite similar to regular flush toilets. There are even micro-flush remote composting toilet units which use a small amount of water, and look nearly identical to regular flush toilets.

Self-contained composting toilets are generally cheaper to use and easier to install than remote composting toilets. However remote composting toilets are able to serve more users and are often easier to clean and maintain than self-contained units.

Common Problems with Manufactured Composting Toilets

Manufactured composting toilets are wonderful in many ways: they save water, produce a valuable end product that benefits the environment, lessen pollution and can even save on money (despite their initial costs).  When installed and used properly they should be completely odorless and produce rich, fully composted humus that is easy to remove from the toilet and use in your flower gardens (or elsewhere).

However, many users of manufactured composting toilets by Sun-Mar, Envirolet, BioLet and other composting toilet models have had less than ideal experiences with their composting toilets.  As with the problems with homemade composting toilets that I have discussed in my personal account of using a humanure homemade composting toilet, the problems with manufactured composting toilets are frequently due more to user error than due to a problem with the toilet composting system itself.  Still, these problems are common enough to suggest that there needs to be made more effort on the part of manufacturers to properly educate consumers about common problems with these systems and how to avoid them.

Here are some of the common problems users report with different manufactured composting models – as well as some ways these problems may be remedied or avoided altogether.

1. Problems with liquid build up in the composting toilet.

This is by far the most common complaint I have common across in my research of manufactured composting toilets complaints (it also was a problem I experienced with homemade composting toilet buckets, but due to their small size and frequency of being emptied not as significant of a problem, I think).  This fluid is generally a result of people urinating in the toilet.  The composting process will simply not work properly in most composting toilet systems if there is too much fluid in the system.

Some users, and even some manufacturers, recommend not using composting toilets to urinate in, but this does not seem like an adequate solution to me (and many other users).  Particularly for females, it is a hassle to have to urinate in a separate container or outdoors (not to mention that this may be illegal in some areas).  Excess liquid can be controlled, however, by adding adequate amounts of dry material to balance the composting matter and using electric fans and heaters to help evaporate and dispel excess moisture (so for those purchasing non-electric models, extra care will have to be taken to keep the system in order).  In addition, there are now models being manufactured that divert urine away from the “dry” composting area (for fecal matter).  For an example of this system, check out the Nature’s Head composting toilets.

2. Problems with Odor.

A well functioning composting toilet (whether homemade or manufactured) should be odorless.  Odor problems are a sign that there is a serious problem with the system.  Frequently this is due to the liquid issues discussed above.

Composting toilets rely on aerobic decomposition, but with excess liquid, the process will instead convert to anaerobic decomposition (for a discussion of these two processes, read “How Toilet Composting Works“).  Both of these decomposition processes are found in nature, but anaerobic decomposition is the the smelly one, and if your toilet has gotten out of balance, the smell can be quite bad indeed.

To remedy this problem, you need to get your compost back in balance by adding dry matter to it.  Unfortunately, if it is really bad, you may have to remove some of the liquid matter first – a quite unpleasant task – so it is best to try to keep this problem from developing in the first place!

3. Problems with removing the finished compost from the toilet.

There are two significant problems users may encounter when it is time to remove the compost.  First, we return again to the issue of excess liquid – if the mixture is too wet, it will be difficult and smelly removal process (and you may well decide to remove the toilet along with the compost!).

A second issue some users report is a result of overloading the system.  For most composting toilets, you need to make sure the finished compost is removed promptly.  You may also be able to make the process of removal easier by using very lightweight organic brown matter for your dry matter in the composting toilet.  Peat moss may be an ideal medium for most composting toilets (although there may be concerns about using it due to environmental issues).

Switching to any toilet composting system – be it homemade or manufactured – requires a significant change in practice and much education.  Anticipating what are very common problems by users, and providing full disclosure of these issues are and how to resolve them, would be a great benefit many users of these toilet composting systems.  Furthermore, it would also help promote composting toilet usage instead of leaving some composting toilet users frustrated, angry and often abandoning and discouraging others from using a valuable green technology.

For more information about composting toilets and reviews of different composting toilet systems, please return to the Toilet Composting Home Page.

Frequently Asked Questions about Composting Toilets

If you are just learning about composting toilets, or have an interest in purchasing one for your home, cabin, boat or RV, you are likely to have many questions.

Below you will find links to articles from this website answering some of the most common questions I have encountered regarding composting toilets.  (If you are unable to find an answer to your question, or have questions or comments about the answers I have posted, feel free to send me an email using the contact information provided above):

  1. Five Top Questions about Composting Toilets.  Fast answers to some of the most common questions people have about compost toilets.
  2. What are Composting Toilets? A discussion of the basics of a composting toilet system and how it works.
  3. What is Humanure and What Can I do With It? Answers questions about how to use and the safety of the compost produced by composting toilet systems.
  4. What Can You Put in a Compost Toilet? Besides the obvious (human waste, toilet paper), there are many other ways most composting toilet systems can be used to process organic household waste.  This article discusses the many different ways you can use a compost toilet in your home.
  5. How Much Do Composting Toilet Cost? If you are considering purchasing a composting toilet, you may initially be surprised by the price tag.  But composting toilets are actually an excellent investment for your home, and this article explains why.
  6. Where Can Composting Toilets be Used? You may be surprised at all the locations suitable for composting toilets.
  7. What is Wrong with a Flush Toilet? Read this article to find out.
  8. Are Composting Toilets Safe? This article answers some of the concerns you may have about the safety of composting toilets and humanure.
  9. What are the Environmental Benefits of Composting Toilets? An excellent discussion of why composting toilets are a good choice for the environment.
  10. Where can I learn more about composting toilets? For more articles about the fundamentals of composting toilets and how they work,  check out the “Composting Toilet Basics” section of this website.  To learn about what kind of composting toilet system is right for you, you should check out “Composting Toilet Systems.”  If you are interested in reading reviews about different manufacturers of composting toilets, check out the “Composting Toilet Reviews” category of this website.  There are also pages devoted to documenting many Online Resources for composting toilets, and suggestions for Books on Composting Toilets that you can read.  You can also return to the Toilet Composting Homepage to read the most recent posts about composting toilets.

1 2 3 9