Compost Toilet FAQs

Compost Toilet

Compost Toilet FAQs

Is a compost toilet legal?

Yes, it is legal to use a compost toilet in a home and many other locations, but local municipal and city authority rules on how it should be used must be adhered to.

Why should I get a compost toilet?

Firstly, because it is good for the environment.  From a more practical standpoint, a composting toilet can provide a way for you to safely process human waste in places where conventional disposal systems such as sewers or septic systems cannot be used.  It is also a much more economical solution for locations such as cabins, vacation homes, or boats where toilet use is not that heavy.

How long has the compost toilet been around?

Composting human waste is not a novel idea. It has been happening all over the world for thousands of years. Henry Moule developed what is called the dry earth system during the cholera epidemics of 1849 and 1854. He patented the process in 1860.  His system was adopted in homes, military camps, and hospitals.  The first commercially available composting toilet was manufactured in Scandinavia in the 60s.  Canada and Australia have become leaders in manufactured composting toilet systems.

How much does a compost toilet cost?

Prices vary depending on the unit.  Some simple self-contained toilets cost around $750 and more sophisticated systems run around $1,000.  The true cost savings are realized over the lifetime of the unit, with reduced water and virtually non-existent waste removal costs.

Does a compost toilet stink?

A compost  toilet is a far cry from an outhouse.  Human waste smells because of its anaerobic bacteria which produces organic compounds and inorganic gas hydrogen sulfides.  When waste enters the tank of a compost toilet, the bacteria responsible for the odors die in the presence of air and are replaced by aerobic bacteria.  The aerobic bacteria are what turn the waste into humus, and they do not produce any odor in the process.  Most compost toilets have fans connected to vents that remove any offensive odors.  If your compost toilet smells, there is something wrong.

Will a compost toilet clog up?

Your compost toilet will only give you problems if it is overloaded or not properly maintained.  In most cases, it will handle those times when you are entertaining guests, and they system is used a little more than usual.  To keep your unit operating without any troubles, it is important to follow manufacturer’s guidelines.  The specifications for your compost toilet will specify rated capacities that will tell you how many people can use the system.

What is left when the waste has been composted?

Humus is a dry fluffy material similar to garden peat moss.  You will be surprised what the humus looks like.  Compared to what goes into the unit, humus has only a slight musty smell.  It is compost, and it is good for your garden.

Where can the solids be emptied?

Always follow the instruction provided with your unit.  In general, you may bury the humus in your garden or sprinkle it on top of the ground depending upon local codes.

How frequently must the tank be emptied?

Of course, this depends upon your usage of your compost toilet but a typical unit, when used by two people, should only need to be emptied about once a month.

Can I turn the fan off when the toilet is not being used?

This is not recommended.  You may notice a musty smell while the fan is not running.  Also, the fan helps to introduce air and moisture into the tank which is necessary for the decomposition process.

When should I not use a compost toilet?

Probably the biggest issue is heat.  Cold environments are not good for the bacteria that break down the waste.  The bacteria do best when the temperature is 70°F or warmer.  Temperatures below 50°F will probably cause composting to stop.  The toilets themselves can freeze but not when they are actively compositing.  Composting toilets may also be an issue in dwellings such as apartments or townhouses.

What can you put in a compost toilet?

A compost toilet will compost anything organic.  So things like food scraps, egg shells, paper, cardboard, lawn clippings, disposable cotton diapers and tampons (without the plastic tags).  Remember though that you cannot exceed the capacity of the toilet.  So you might find a separate compost pile a better place to dispose of these other items.

Can I use toilet paper?

Just like human waste, toilet paper will compost, so you can place it in your compost toilet as you normally would.  Obviously less paper is better!  Paper typically does not compost as quickly as human waste and might be visible long after the waste has been broken down.  All types of toilet paper can be used but try to avoid perfumed or colored paper.  Pick those brands that are labelled “safe for septic tanks.”

What about “unusual” human waste?

If they are organic and do not exceed the capacity of the toilet, then unusual waste can be composted.  Typically these sorts of wastes are not common unless someone in the home is sick and are unlikely to affect the function of the toilet.  Some of these wastes may increase the wetness of the material being composted.  This situation can be corrected by introducing a small amount of sawdust or peat moss.

Waterless Toilet

Please continue reading my Composting Toilet – 2 product review and visit my Compost Toilet Store. Also see my other review posts for this green living product: 

Fifteen best features of composting toilets.

How composting toilets work.

What makes a composting toilet green?

Composting toilet tips and tricks.

Thank you for visiting, and for supporting Switch it Green, Switch it Forward.


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