Question

Are incinerating toilets really an option?

Asked by Bonnie Tyler
Beaverton, OR

How do they really work?

Answer

Elizabeth DiSalvo

Answered by Elizabeth DiSalvo

Norwalk, CT

Trillium Architects

January 28, 2013

Incinerating toilets are an alternative answer to a standard plumbed, water closet. 

  • They don’t need any water and they do not need to be hooked-up to a sewer system or septic system.
  • They rely on electric power or natural or propane gas to incinerate human waste to sterile clean ash.  (wow! burning poo!)

I used to live off the grid in Colorado and it was absolutely normal to not have a real toilet in your house. Many people had out houses or composting toilets. I knew one incinerating toilet.

  • Basically it is a ‘hot’ idea because if you really are trying to live off the grid or if you live in a remote location where the ability or cost of getting utilities, especially plumbed water, to your site is daunting, this is a problem solver.
  • Also, incinerating toilets take up a lot less room than a composting toilet and require considerably less care and maintenance. No more churning and shoveling out composting toilets. That feature alone makes it desirable.
  • Great applications include camps, cabins, fishing shacks, dune shacks, accessory buildings etc

Incinerating toilet come in two types – electric  or gas.

Electric toilets

Electric toilets are easy to install, require no water or plumbing. Electric toilets only require a 120v outlet and a 3 inch exhaust pipe to the outside of the house. (Preferably the exhaust pipe goes above the roof line for optimal draw for the exhaust and odor control.)

Electric  toilets also are similar to ‘normal’ toilets.

  • They have a bowl and a flush mechanism ( a pedal on the floor). 
  • They require a paper bowl liner be put  in before each use, but this is a feature that you will be thankful for because it keeps the bowl clean, remember there is no water rinsing it all away.

The bowl dumps into a holding tank and burns at a scheduled interval for about an hour to reduce the waste in the tank to a mere spoonful of ash. They have something similar to a catalytic converter to control exhaust and odors.

The price range is in the $1500 - $1900 range and costs about 28 cents per burn.

Natural Gas and Propane Incinerating Toilets

These do not rely on the use of water, plumbing or electricity. These systems can be installed any place where a natural gas or propane source is available.

One big difference between electric and gas is that the gas toilets do not have a bowl. They are much more like an outhouse.

  • There is simply an opening and a dry pit below. There is also no water like you would find in a port-a-potty.
  • This feature, combined with the fact the you have to turn, look into the hole and spray a layer of foam over your recent deposit,  is considered undesirable by a lot of people.
  • The sound and experience are just too far out of the ordinary.

The gas units cost a few hundred dollars more than the electric and burn for longer periods of time. They have to be more carefully installed and exhausted and need to be inspected regularly. It cannot be installed in an airtight room as it needs continuous make up air and venting. The foams needed for operation are a continuous cost.

The one great thing about the gas toilet is that it can go places where an electric toilet cannot, because there may be no power lines and no sun for a Photovoltaic Panel.

With both electric and gas versions, exhaust must be carefully located and planned or fumes may be more a part of your life than is desirable.

Building codes

One road block that one may encounter in the endeavor to install an incinerating toilet may be local building codes.

  • Not all municipalities welcome these sorts of alternative technologies.
  • Or sometimes they are ok with them but the code reads that in order to get a Certificate of Occupancy you must have one working , plumbed toilet.

There are many communities that have altered their codes to accept only incinerating or composting toilets (and some may argue that all should as it takes a great burden off of the local septic, sewer systems and water table) , however many communities aren't there yet.

There is always a chance that you can get your local officials to change their minds or make an exception if you provide enough precedent. 

Good luck!

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