Tested: Natures Head compost toilet

Most people I know avoid all the fuss by using their RV toilet only in emergencies and only then for liquids. We have children.

Until recently, the dump point ritual was as much a part of our motorhome adventures as the distinct aroma of a full RV toilet during summer…. but not anymore! Enter the composting toilet.

The composting toilet is not a new concept for houses but it’s only recently that two compact versions (Natures Head and Air Head, both made in North America) have become available Down Under for the RV and boating market.

Priced at $1260 and $1395 respectively, they both offer a similar design as well as a solid, five year warranty.

There are two big differences between a composting toilet and a traditional, holding tank type toilet. The first is the composting system uses no water. The second is the ‘poo’ is separated from the ‘wee’, which offers all kinds of advantages when it comes time for disposal.

In a traditional toilet, solids and liquids combine to become sewerage - an entirely unpleasant substance which is noxious in odour and has a tendency to splatter when poured away.

This means absolutely nobody wants to do this job, so things get left until the removable cassette is so bloody heavy only one person can do that job and I will give you one guess as to who that one person is…

A composting toilet by contrast separates the solids from the liquids as you go, so you’re left with the easy to delegate task of pouring away sterile liquid waste every few days from a discrete eight litre canister.

This liquid can be poured into any available toilet or diluted and safely tipped onto a handy lemon tree or some other shrubbery. 

As for the solids, you get up to 80 ‘goes’ so rather than having to deal with the horrible stuff every three to four days (for a family of four), it’s more like a fortnight between ordeals and in all honesty, it’s not actually that bad.

We installed the Natures Head unit some months ago in our second-hand Winnebago motorhome, and after using it all through summer, the toilet has exceeded expectations.

The main holding tank for solids is prepared with a pre-moistened $2 brick of peat moss or coconut fibre (coir brick) which provides a foundation for ongoing deposits.

After each use, the peat is turned-over using a crank handle and toilet tissue can be used as normal and deposited in with the solids for composting.

We chose the Natures Head unit due its slightly smaller footprint (450mm wide x 475 mm deep) as we have a very small space for our toilet. The width of the Air Head toilet can be reduced from the standard 480mm to 380mm, but you have to replace the crank handle with a standard 10mm socket and ratchet.

Of course the real boon of the composting toilet is that it uses no water, apart from some minimal spray-rinsing of the bowl after use.

An RV has limited water storage so the last thing you want to do is flush 10 litres-plus down the toilet which could otherwise be used for drinking, washing or cooking.

I can’t say exactly how much extra water my children flushed down our old toilet but we’re getting an extra two days from our water tank since swapping it over.

Admittedly, a family of four using the composting toilet full time doesn’t allow the matter sufficient time to break down properly before the system gets full but even so, the odour is surprisingly negligible.

Both the Natures Head and Air Head dunnies use a small low draw fan to keep a negative pressure on the waste holding area, thus preventing expanding gas from entering the RV living space.

Only in the absolute height of summer when the toilet had been in continuous use for two weeks could I even detect any odour and I have a country nose that can detect a daggy sheep at 400 metres!

If you like the idea of emptying your toilet less, having little or no odour, more water for drinking and some really fertile compost to mix through your garden soil, the composting toilet could be just the ticket for your RV too.

NSW-based Kimberley Kampers, regarded as the ‘King’ of off-road campers, are the first Aussie RV manufacturer to offer Natures Head as an option on selected models from their 2015 range, and there’s no good reason why other RV manufacturers won’t follow suit.

The alternative toilet is just as easy to retro fit to your existing setup DIY, with the possible added benefit of freeing up space where the factory-fitted toilet cassette previously sat.

The Natures Head unit is available in Australia from Enviropro.com.au