Notes on installing composting toilet

[Bill McClure]

Just finished installing an Airhead composting toilet in my '98 26X. It's been aboard and in weekend use for the last several months. It replaced the original porta-potti when the aging plastic bellows split. I'm very impressed with how well the Airhead works (no smell even without the vent hooked up) and how helpful Geoff, the owner/inventor was when I had questions. Here are a couple of notes on installation that others may find useful.

The toilet moved around just a little bit when I used the included #10 screws to hold down the brackets. The floor is too thin to countersink them. Some guests found this slight motion unsettling. The underside of the floor can be accessed from the compartment just forward under the dinette seat. I used #12 3/4" flathead machine screws with 1" washers on the outboard side to secure the brackets from the underside of the floor. There is room to reach under there with a ratchet wrench. A structural member limits access on the inboard side, but there is room for a 1" wooden block to take #12 3/4" wood screws. Liberal applications of 5200 to the floor and bottom of the brackets helped seal and secure everything. This also allowed the toilet to mount against the bulkhead so foot room is maximized and the door can be closed. The toilet now feels very secure and there is maximum room for feet and torsos.

The toilet comes with a crank handle to mix the compost. Geoff will substitute an adapter that lets you use a ratchet wrench instead. This is much more compact and lets you center the toilet for more foot and elbow room.

The included vent adapter fits the common Nicro 3" vent. However, with it, the hose sticks straight out in a big loop the gets in the way of your head. Geoff also has a vent adapter where the hose comes out the side. It makes for a very neat installation. I used a second Nicro interior trim ring inverted to allow me to take the vent adapter off and on. Velcro secures them together.

I put both the crank and the hose on the outboard side of the toilet. This takes up the least space and seems to most out of the way.

I was hesitant to spend $1000 for a toilet. It is the most expensive mod I've made to the boat to date. However, it's been worth it, so far. Life aboard is much more pleasant, and female guests have been much more willing to go sailing. It's a great conversation starter at the dock when people ask me where the pump out/dump station is located. This month's issue of Good Old Boat also has an article about installing one.

[kelseydo]

Bill,
Good report. Did you go with the marine or standard seat? I also installed an AirHead a few months back and am pleased with the product (Pics in Mods). Geoff's support was excellent. Just returned from 4 days on Lake Powell, 2 days of which added a couple. With the three of us concentrating on staying hydrated we filled the liquid tank in 2 days. Not a big deal finding a floating crapper and easily emptied the bottle. I do notice some odor from the liquids exiting the vent occasionally on hot days, but not as bad the constant odor of a porta potty. A tablespoon of chem toilet treatment in the liquids bottle helps. In my arid location I find it necessary to regularly add water to the dry side, not a bother, and am amazed at the lack of odor.

Less time dumping = more time sailing.

Dan

[fishheadbarandgrill]

Has anyone put one of these in a 26M?

Bob

[jschrade]

How can collecting your urine in a bottle be any different that collecting it in a portapotty?

THese things are a lot of work and as a weekender, it seems like significant more work than a pump out.

Jim

[Catigale]

...less chance of mixing up bottles and accidentally drinking it??

[Bill McClure]

One of the things that makes this type of composting toilet easier to live with than a porta-potti is that is separates the urine from the feces. Apparently it the combination of the two that makes outhouses and porta-potties smell so horrid and need chemical deodorizers (which smell pretty bad, themselves). The feces/peat moss combination hardly smells at all, and then of peat moss rather than feces, and I have a notoriously sensitive nose. The smell from the urine collecting bottle can be neutralized by the addition of sugar. I drop in a few sugar packets each time after I empty it, and that makes it smell-free if it's a while before I empty it again.

The urine bottle is legal to empty over board, if necessary. If you do take it to a land to empty it, it's only a gallon or two, and it can be dumped in any toilet. That's easy. I always struggled with the suitcase sized tank on the porta-potti. It was heavy and awkward. It smelled and spillage was a distinct and horrrible possibility while I tried to find a dump station. They are not frequent in Puget Sound, and sometimes they don't work. Then I had to wash the darn thing out. It was a hassle and nasty. So far, the Airhead has been easy to use. Haven't had to dump the compost, yet. But, that doesn't seem like it's going to be a problem, either. The holding tank comes with an airtight cover for transport. There is no liquid to worry about spilling.

I think mine has the marine sized seat. There should be room for the full size if you use the ratchet handle and the side connection vent for minimum toilet footprint in the head. I'm going down to the boat today and will try to remember to measure the seat.

The one thing I do wonder about is the composting activity during the winter. I won't be using it as often, so it may not be an issue. I have though about wrapping a plumber's heat tape, like you use to keep pipes from freezing, around the base if it becomes necessay. They are about $25 at Lowes and can run off the shore power at the boat.

[Bill McClure]

Hi Jim,

I re-read your post and saw that I hadn't addressed your concerns about maintenance, sorry. A major reason I chose a dry composting toilet rather than replace the broken porti-potti was the far less maintenance required. My current use is weekends. I empty the urine bottle over the side (perfectly legal) at the end of the weekend, and I'm done. 30 seconds and four steps. A full bottle weighs about 12 lbs. I have yet to fill mine in a weekend with two people aboard. The estimate for emptying the composting tank is 80 uses. It may be Christmas before I reach that. That will be maybe 20 lbs? of dry matter to lug off the boat and up the dock in a cart. I can dispose of it in the dumpster in a bag. The boat is odor-free when I open it up each weekend.

The porta potti HAD to be emptied at the end of each weekend or the boat was uninhabitable. I had one female guest who refused to come on board once she smelled the odor. That meant lugging 30 lbs of the deadly blue liquid off the boat, up the docks (I'm at the far end, of course), loading it into the car, and driving over to Swantown marina where I reversed the process and carted the tank out to the pump out at the end of the pier, dumped it, washed it out, and then took it back to the boat and refilled the tank. Not much fun in the dark and the rain in November. The porta-potti also tended to not work well (didn't flush). It was a hassle and about $35 to replace the bellows when it broke. It's hard to see how anything on the Airhead could break. No problem to fix if it did, especially as the principal of the company is also the support guy. Trying to navigate the Thetford/Dometic maze to find the right part and a dealer who had it was not easy. So the porti potti took a couple of hours each week and much more labor to maintain than the Airhead. It also cost 1/10 of what the Airhead did, so everyone has to balance the equation for themselves. I just wish I had installed the Airhead last summer when I was spending 4-5 nights aboard each week. Now fuel, food and water are the limits for using the boat rather than holding capacity, and I don't have to find pump out/dump stations.

[innervations]

Reiterating Bob's question. Anyone installed an Airhead on a

[Sumner]

.... My current use is weekends.........

I've been real interested in one of these, but haven't worked out the logistics of how to use it for say 2-3 months at at time of continuous use where it has to be carted off somewhere at some point and the composting process brought to an end and then started again. This would also have to take place on the water more or less or going ashore at a marina as we wouldn't have access to a car during the period and don't stay in marinas.

Any thoughts on that?

We have been using the Double Doddie bags and like them as like on our spring trip it is no problem hauling the waste with us for up to 2 months at a time and they can be disposed of in a dumpster. With the Endeavour we did and will keep using them unless we are over 3 miles out where it is legal to use the ship's regular ...



... head and put it overboard, but even then we still might keep using the bags as we don't mind them.

I would like suggestion on using a composting head for extended trips though,

Sum

Our Endeavour 37

Our Trips to Utah, Idaho, Canada, Florida

Our MacGregor S Pages

Mac-Venture Links

[Laika 26X]

Interesting.
I just happen to be going the same route. Absolutely sick and tired of the Porta Potti I have. Even the built-in Type III MSD I had on my Bristol always stank...regardless of fittings/tanks/chemicals. Perhaps rigid PVC would have helped! Fresh/Saltwater flush, did not make a difference.
I decided to go with Natures Head Composting Toilet. I saw them 2 years ago at Annapolis, and they'll be there this year as well. I like the look and price, which appears to be ~$100 less than Airhead, but you can always bargain. Also, both and had had Natures Head installed, check the Mods under "Head". I plan on picking one up shortly at the show.

...less chance of mixing up bottles and accidentally drinking it??

I'm sure if you "drink" to much.
Great idea, excellent mod. Wish I had one back on the Bristol!
"Sub" Ed

[fishheadbarandgrill]

To double up on what Ed said. I did see a mod for a Nature's Head in the mod section. I'm going with the Nature's Head model with a hard-wired vent fan through the skylight in the head.

Bob

[bartmac]

Just add my 10 cents worth....installed a Airhead compost toilet with the thought of sharing it with our motorhome ie move it from one to the other.What a success compared to the porta potti,no more smell.Not much work looking after it,no need for pump out....definitely recommended

[Retcoastie]

Bill wrote;

The urine bottle is legal to empty over board, if necessary.

and

I empty the urine bottle over the side (perfectly legal) at the end of the weekend, and I'm done.

I had read these statements shortly before going to the "Reading Room" for my morning constitutional. While there I picked up an issue of SAIL magazine, as I have a habit of doing. This particular issue, July 2011, had a question in the ASK SAIL section about composting toilets. Don Casey replied at some length. In his reply, he stated

Despite being sterile, urine is raw sewage as soon as you capture it in a container, so you cannot legally pour it overboard

and further

It seems likely most users are dumping their urine under cover of darkness.

Bill, Don Casey appears to contradict your statements. Could you share with us what led you to believe that dumping urine overboard was okay. I'm not trying to flame you or provoke an argument with you. I am trying to learn. Do you reference a local regulation, a state ruling (if so where) or is this a federal permission?

Ken

[jschrade]

It's illegal to dump urine overboard inside of 3nm's - please I'm just the messenger.

We just daysail and weekend and 2 gallons is not going to get it done with three women on board - I went to 5 gallons! No one has violated my potty by doing the big job in it - I suspect they fear for their lives!!!

I have had to hit the throttle hard a couple of times as they kept the turtle at bay.

Once I get sick of dumping, I will drill a hole and add the pump out. I am thinking of moving to a bigger boat so I am not too motived to put holes the next owner may not want. The head comes with both setups, so it can be added.


Jim

[Ixneigh]

Soooooooo...
That means i cant hang it off the back and take a whiz? Or pee while swimming?
I could see that in a lake but in the ocean? What about the dolphins??
If its just the container bit, pipe it directly overboard?

Ixneigh