I know it sounds self serving for me to tell people that they shouldn’t build their own toilets but hear me out. Live aboard boaters and RV owners are usually very handy. You basically have to be. You’re out in the middle of no-where and something goes wrong and there is nobody you can hire to fix it and no place to go to get parts, at least proprietary parts. When I built the C-Head I kept this in mind and made it so that parts could be easily found at local hardware stores. Having lived aboard two sailboats for a total of nine years, I knew that that would be a valuable consideration for my product by people who would use it. I also knew that because of that, people would try to imitate the design, thinking they were saving money and getting the satisfaction of being creative all in one deal. I mean it’s just a bucket and a jug and a box and a toilet seat, right? But let’s look at that.
More in a multi-part series of articles on ventilation
RVs and travel trailers have a unique set of problems associated with ventilating the toilet. They are the one case where you regularly have 60 mile an hour winds on the outside blowing for hours on end. The other exception being a shack in Antarctica. This of course is what happens as you go down the highway. The problem it creates is negative pressure inside the cabin which allows the positive pressure outside to force itself inside. It will do so by any means possible. If you have ever been driving down the road in your RV and someone uses the toilet and you get a strong blast of stinky air when they flushed it or you just have a constant slight smell of the holding tank present all the time, that is what is happening. As a retired firefighter, I call it “back-drafting.” You have opened a pipeline from the outside to the inside going through the vent pipe and the holding tank and through the toilet dragging all the associated smells with it. The outside pressure being greater than the inside pressure is the force behind it. With travel trailers, it is not such a problem because people rarely ride inside the trailer when you are driving down the road from one place to another. If the cabin of your travel trailer does develop a smell then it dissipates quickly when you open the doors and windows to occupy it.
The first in a multi-part series of articles on ventilation
Ventilation is one of the most complex aspects of any composting toilet system, but it shouldn’t be. Almost all urine diverting standard sized and compact composting toilets require ventilation. In some, like the Separatt, it is the sole means of removing the smell and moisture produced by processing the solid waste. Urine odor can be fairly well confined to it’s container, but pouring it out is a stinky process indeed, unless you have treated it with a holding tank solution. Treating it is common with mobile applications like boats and RVs because public restrooms are often the place they get emptied and you don’t want to chase everybody out of the bathroom and have them complaining to the management. But I digress . . . This is a series of articles on ventilation. First I will discuss boats, except for houseboats with RV type flush toilets that use a floor flange which I address in the Part 2 which is RV and travel trailers. Part 3 will be fixed applications like homesteads, cabins, tree houses, etc and Part 4 will be prepper bunkers which are a special case and Part 6 is tiny houses, also a special case.
One of the great advantages of the C-Head is the ability to easily funnel the urine out of the toilet into an outside receptacle such as a black water holding tank like those found in boats and RVs, or an agriculture type storage tank for permaculture use or into a drain field. You can do this using what we call the “bottom exit kit.” In addition to home and cabin installation, this can be done with most RVs, travel trailers and houseboats that have an original, factory installed toilet that flushes into a holding tank through a standard toilet flange that is mounted on the floor. Diverting urine to the holding tank in its concentrated state takes much longer to fill the the tank up and thus significantly extends the time between dumping the tank . In addition, it makes the disposal of urine much easier for both boondockers and for RV and travel trailer owners who prefer to use dump stations. More on that in a minute.
“The time has come,” the Walrus said, “To talk of many things: Of shoes–and ships–and sealing-wax– Of cabbages–and kings– And why the sea is boiling hot– And whether pigs have wings.”
The Walrus and the Carpenter – Lewis Carroll
So now we have to get a little personal. Having spent a lifetime directly involved with hands-on medicine as an Army Special Forces medic and as a municipal and then county firefighter/paramedic, and having been married three times, I thought I knew pretty much everything about female anatomy . . . well almost everything. But once I got into the toilet business, I found out some things that I didn’t know and that were surprising. Number one, as many women order my toilets as do men. It may be because, between the two of them, she is the one with the bank account. More common than you would believe. And number two, women’s anatomies are significantly different with respect to what we call “directional stability” in the boat design business. And number three, when women go to the bathroom (#2), they usually don’t go #1, then #2, nor do they go #2, then #1. They usually go #3. That proved to be a challenge that I hadn’t expected to have to overcome.
David Goodman (AKA “David the Good”) and I have been communicating off and on for several years. He used to live about 30 minutes away from me and while we had a couple of phone conversations, somehow we never managed to get together until he and his family were on their way to their new home in the tropics. I’m still not sure where he wound up exactly but from the pictures on his blog, it looks like a piece of paradise.
The C-Head toilet is available with two options regarding the processing of solid waste. The churning version and the churnless version. One has a churning mechanism to move the medium around (medium = sawdust, wood shavings, peat moss, coco coir, etc.). The churnless does not. Each has its advantages and disadvantages over the other. The difference in cost is $35 with the churnless version being cheaper, so if you are uncertain which version would work best for you, we suggest you get the churning version and modify it into a churnless version for testing. You may want to convert the systems back and forth depending on who is using the toilet. For example, if you are having guests who are not used to using a C-Head, you may want to use the churnless version during their stay for a couple of reasons. So let’s look at the differences.