Composting Toilets

[DonPowers]

I'm looking into the Sun-Mar Compact Electric composting toilet for the garage. Anybody here have any experience with them or other brands?


http://sun-mar.com/prod_self_comp.html

 

[Jess]

I don't have direct experience, but my neighbours at the cottage went with the Sun-Mar and for light use, it worked reasonably well. They did have problems with excess liquids and in the end bucked up for a proper septic design and installation. The other one down the way was one with a separate tank and had the ability to spray the RV type bowl clean after use. It only survived a summer and was replaced because their guests couldn't figure out that more water isn't better in a composter. Where I once worked, we had remote sites with the propane Destroylet toilets, went to composting types and they worked ok for the informed. When somebody that didn't have to take care of them used the toilet, they were a mess. Your results may very, but if possible, I would do a septic connection or pump to the sewer.

 

[SteveCh]

We have one for our home, and it's the only toilet. It's all we've used since 1985. We had another brand back then and I switched to the Sun Mar in maybe 1990 or so. Just my wife and me and the occasional guest or two are here, and the self-contained models such as ours are ok for that. However, for any greater usage you would need one of the models which has a toilet in the house and a larger container beneath the floor or outdoors in a shed or closet or something. The toilet empties into a pipe which carries the material to that outdoor container, where the composting takes place. Those models can handle quite a lot of use, or so I read.

As far as excess liquid goes, the self-contained units have an outlet at the base on the backside, and you are supposed to run a tube from the outlet to the outdoors and use a "dry well" sort of thing, such as dig a hole maybe the size of a five-gallon bucket and fill it with rock, cover it with whatever, very simple technology. I have my hose running through the wall to the outdoors, maybe three or four feet total.

 

[DonPowers]

Thanks guys.

The model that I'm looking at has a vent fan and electric heater to evaporate the liquids along with the drain tube for excess liquids.

We have a regular toilet in the house and the garage unit will be for occasional use and will see surges when the kids and grand kids are here for visits.

 

[SteveCh]

Yes, that is the model I have and was referring to previously. I would think you will be fine with that one. We, the two of us here, don't really have the need of the excess-liquid tube, but there have been a couple of occasions with guests that required it.

Seeing you live in sometimes very cold territory: if your garage or wherever the toilet will be located is not heated, the composting activity will come close to ceasing during the cold times. The bacteria which do the work like warmth. The heating element in the base of this model, which I believe is 250 watts, will help evaporate the liquid which is pooled in the bottom of the toilet housing. The resultant "air" will then exit via the vent with the fan's help. I can't predict how much that heated air down there will assist in keeping the bacteria happy. Meaning, not much composting gets done in the winter in unheated areas. You should still be ok if it is only getting occasional use.

Also, some manufacturers state that one can put toilet paper into the composter and have it composted. They usually recommend single-layer paper. We have found that, at least in our home, this paper causes a mess and really does not compost well. We keep a bin next to the toilet and advise guests that all paper goes into that trash can.