Composting Toilet Q & A

Composting Toilet Q & A

James Completes a Composting Toilet Change-Out

When Ashley and I bought our used Airstream in 2017, it came already equipped with a Nature's Head composting toilet. The previous owners had it installed at the time of their purchase of the trailer new. Ashley was excited but I was a tad apprehensive. After the first month of personal experience with it I became as happy as her.

Top Questions and Answers from our Personal Experience

  • Why would you even want a composting toilet?
  • Eww isn't it gross?
  • How often do you have to change it out?
  • Is the compost usable?
  • What do you use as substrate?
  • What problems have you had with it?
  • What about maintenance and repairs?
  • What if my bowels are jacked up?

Why would someone even want a composting toilet?

Independence. What if your black tank is full and there is nowhere to dump it? An RV rigged with a composting toilet has an unused blank tank. That empty black tank can easily be connected to your grey tank (sink and shower) with an external adapter. This allows one to boondock twice as long without having to dump tanks at a dump station. Living off grid, we find it is a nice option for conserving water and managing waste. We have a septic tank in the ground a Strand Farm but we only use it for grey water.

Eww! Isn't it gross?

This is exactly what I thought when it came into my possession. At first I was thinking- this is a little strange peeing while sitting down and stirring my poo? I opened and closed the chamber hatch so quickly, not wanting to see what was going on down there. Urine was not too big of a deal since I handled pee jugs all the time as a nurse. To my dread, the time arrived to empty the bin and start afresh. I picked up the toilet and brought it outside for the job. I held my breath and popped the top off peering inside like a bug that can't help but fly towards its own electrified death. What's that smell? Smells like soil. Where is the poop?! Looks like soil. I was blown away at how manageable the change-out was! It turns out that when urine and poop mix that is when you get that nasty smell. the composting toilet keeps these separate allowing the solids to begin composting.

For those 4 years stay at various RV parks around the US we witnessed all kinds of nasty situations with our neighbor's black tanks (a black tank is the container that poop and pee and water would go into if you were using a standard RV toilet. (Think Porta Potty). Super horrendous sewage stench would waft in through our vents sometimes when others are emptying their tank. Every so often a neighbor's sewage hose would come apart during emptying. Remember uncle Eddy from National Lampoon's Christmas Vacation?

Black Tank scene from my favorite Christmas movie of all time.

How often do you have to change the collection chamber?

There are several factors that effect the timing of change out. The type and quality of your substrate, you and your families bowel habits, the consistency of your stool. Not to mention, your lifting ability. Our toilet weighs about 22lbs while empty and closer to 50lbs when full.  For us, now that we are homesteading the average change-out is ~4-5 weeks. The urine jug needs to be emptied every 2-3 days in my household.

Is the compost usable?

Yes, but it is nuanced. Have we used ours for anything? No, not yet. Up until we planted our Airstream in the soils of Strand Farm we had moved too frequently to properly complete the process. "Solids that have not fully composted for at least a year are not suitable for use on ingestible plants" per the manufacturers website. We have not set up our permanent bin for the composting toilet contents so we have 5 months of compost temporarily stored at the farm. Our plan is to have this squared away in the Spring of 2022 See our Roadmap.. We do not plan to ever integrate any of this compost into any of our edible gardens.

What do you use as substrate?

We use compressed coconut core fiber. There is a brand on Amazon that is highly reviewed called Kempf Compressed Coco Coir. However, In 2021 the quality of this brand went down the toilet. We received two batches of this stuff that would not expand nor absorb when you added water for reconstitution. Currently, we are using a brand we found at a garden center in Boise, Idaho when we were traveling last year. Your substrate is a kind of  Goldie Locks situation where it needs to be not too dry nor not too wet. You'll know when you turn the agitator handle when a change-out is due.

What problems have you had with it?

The problems we've had with it are all operator error. It is important to keep tabs the fullness of the urine jug. Overfilling it will contaminate your compost and cause an instant sewage situation. Rule of thumb never go to bed with a near full urine jug or you are fixin' for a early morning or late night urine jug emptying mission. Another issue we've had is ensuring guests are properly educated on it's operation and comfortable using it. At some point we will create a laminated cartoon card instructional. People tend to be particular about their regimen and find the task daunting.

What about maintenance and repairs?

We can only speak for our Nature's Head toilet. But repairs have been minimal. There is a little computer fan in the toilet at the vent that is powered by 12V that went bad on us. Another time we lost a piece to the agitation handle. This summer we noticed the moisture seal where the upper and lower part of the toilet connect was starting to degrade. For all three of these separate instances we sent an email to Nature's Head customer support and new parts were sent to us without question. We are very impressed with the little maintenance required by our composting toilet.

What if my BMs are off?

The more liquids placed into a composting toilet the more supplemental dry substrate needs to be added, necessitating more frequent change-outs. A spray bottle with water and some vinegar works great when we are not working so well. ......................................................................................................................

VHS Movie of the Week:‌‌ National Lampoons Christmas Vacation