Airhead Composting Toilet

SunMar composting toilets are well known, but this one is new to me. Seems to be primarily for boats, but some people apparently use them in tiny homes.

   “A workable system for small to medium sized boats, giving even pocket cruisers the independence of a large vessel”

About Lloyd Kahn

Lloyd Kahn started building his own home in the early '60s and went on to publish books showing homeowners how they could build their own homes with their own hands. He got his start in publishing by working as the shelter editor of the Whole Earth Catalog with Stewart Brand in the late '60s. He has since authored six highly-graphic books on homemade building, all of which are interrelated. The books, "The Shelter Library Of Building Books," include Shelter, Shelter II (1978), Home Work (2004), Builders of the Pacific Coast (2008), Tiny Homes (2012), and Tiny Homes on the Move (2014). Lloyd operates from Northern California studio built of recycled lumber, set in the midst of a vegetable garden, and hooked into the world via five Mac computers. You can check out videos (one with over 450,000 views) on Lloyd by doing a search on YouTube:

6 Responses to Airhead Composting Toilet

  1. A friend of mine has recently installed an Airhead in her housebus… it works well and the little fan which is active 24/7 ensures there's no unpleasant odours. Another friend has one in his liveaboard cruising yacht, they're a family of three who use it with no problems. They even describe using it as a pleasant experience…
    As with all things, follow the instructions for installation and use and all will be well…

  2. The Air Head is good as is the Nature's Head (which I sell Both are U.S. made.
    I've asked the manufacturers to change the design to allow for easier emptying but they're not changing anything any time soon. (Here's my friend and first customer discussing life with composting toilet on his sailboat:…/NaturesheadOnBoat2.pdf‎)
    That's too bad because I could sell a lot more if they'd change the design.
    These units are a little small on capacity for a year-round tiny home used by more than one person. The Separett Villa and DIY urine-diverting toilets are often chosen by owners of small houses with more than one inhabitant. I'll soon post a photo of my tiny house dwelling friends discussing their toilets (Villa and DIY) and their maintenance.

  3. I recently installed an 'Airhead' in my small housebus. I gave it a lot of thought and researched it and read everything I could find about it before I bought one. The theory of it is great… In practice I think there is lots of room for improvement. The device the crank handle is attached to, that stirs the 'solids' so they mix with the peat to enable composting, doesn't reach the bottom or sides of the solids holding tank. Therefore the capacity is diminished as only the centre part of the tank is being mixed. Also the instruction book says to empty the holding tank when it is filled to 2 inches of the top. When it is this full I find the fittings above this level – the crank handle, and the lifting handles, leak… Not at all nice. I thought all fittings would be liquid tight.
    I read that people use them 'for a season' before emptying. Mine lasts me – one person – for 3-6 weeks. And I do not fill it up with toilet paper!
    So would I buy another one? Well I'm 60% happy with it.
    Anybody else had 1st hand experience with one?

  4. I think the Airhead came first and Nature's Head adapted the design. My understanding is that the Airhead urine tank can be emptied without having to lift the whole top of the toilet (unlike the Nature's Head), but both essentially do the same job. They are compact which is great where space is limited. I prefer the Separett Villa which is technically a collection unit as composting doesn't happen in the toilet – very neat with the 'concealing screen' great for those phobic of compost loos. In my experience, the 'bucket' will collect 4-6 weeks worth of 'solids' from one person before needing emptying. When the manufacturers quote a 'seasons' use, I don't think they are referring to it being used constantly – maybe weekends only???

  5. As the manufacturer of the "Air Head" composting toilet we take all owner concerns seriously and have a lot of success in dealing with our customers directly. I contacted "Licorice Allsort" though her email to address her experiences stated above with the "Air Head" composting toilet and after several email exchanges I was able to come up with five changes in regard to use and installation that she could to to address the problems she is having. Currently she is not on the road and therefore not using her toilet but has agreed to try the recommendations I made when she starts up again. As the posts higher up seem to suggest, this unit was operating significantly below its typical performance level. The most efficient means of getting problems addressed is directly through our website The lag between her post and my response is simply because I was not aware she was having any problems. We cannot and regularly sweep the internet for customer complaints. So for fastest results, please contact us directly, we are happy to help.

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