Buyers’ Guide: Doing the numbers on caravan toilets!

ByTim ScottJuly 31, 2020
Buyers’ Guide: Doing the numbers on caravan toilets!

We all have to go, but how you do it depends on what toilet option you choose, so we’ve run the numbers on caravan toilets for your convenience.

In the evolution of camping toilets, we’ve come a long way. Well, most of us have. There are still people who leave the white bush streamers – as opposed to steamers (and if yours are white, see a GP) – to indicate that the intrepid who follow should watch for more than a king brown if walking this way. Look, we’ve all been caught short, but surface dumping must not be a first-choice for reasons that should be obvious, but …

As nature intended?

The original method is a bush poo. We won’t worry about the number one’s because as long as you’re not pouring directly into someone’s drinking supply, most plant life in Australia will welcome a drink. Still, use common sense around watercourses, eh? Just because it’s liquid doesn’t mean you’re helping by boosting the volume a little. Who knows what you have in your own system or where the water goes.

If you have no toilet facilities with you then use this as a rough guide: a shovel, a brisk walk 15-20 metres from any watercourse, dig the hole a good 20cm deep, do what you need to do and add your paper to the hole’s contents and then burn the paper with a lighter. That way, if an animal digs up your doings, the paper won’t decorate the landscape. And finally, backfill with soil (the hole).

There are some great ways to ease the squatting process, with home-made bush dunny seats, dedicated stools (sorry) and even the towbar-mounted seat over a short-drop into a bag-lined bucket. Do what you need to to do, but don’t leave anything behind.

Thetford Porta Potti


The porta potti, a generic term now bestowed upon a portable toilet whether it’s of the Thetford brand or not, is easy to transport and has been a mainstay of the caravan and campervan world for ages. It’s easy to keep it stored in a locker, out of sight, but unless you have a dedicated toilet tent outside, it’s in close proximity indoors and use can be less than, let’s say, dignified. The portable toilet is easy to clean, but given its low height not as easy to use for some if your mobility is limited. If you like to mix it up, and tent camp sometimes, or hop into a camper-trailer or van sans ensuite, then a portable toilet may be a huge benefit. Pop-up tents for this extra ‘little’ room are readily available and the portable unit is always a good back-up for kids sleeping outside a caravan in swags or an annexe. Advantages of this style are it uses less water and emptying it is simpler than some fixed installations, although on the downside, it will require emptying more often and that’s usually not a pretty exercise.

If you’re a regular camper, then you will likely look at the most common installation of all RV toilets:


420x400 C402 Open With Tank Thetford C400 Standingholding Tank Hr Copy

The cassette

When perusing shiny new RVs for the next chapter of your camping lifestyle it’s easy to see the white expanses of bathroom surfaces, the shower, the taps, the ceramic bowl, mirrors, etc, and visually clock the toilet bowl, or seat cover. It looks familiar, you have one at home, but then comes the realisation that you have to empty it yourself! This may happen on the dealership floor, the realisation, that its, not the action, or it may happen at about your third or fourth night away. Your salesperson showing you through the caravan may not wish to break from the dream-selling and assume that you know how the toileting routine works, but you know what happens when you assume something, don’t you?

Aef Avida 15

Your cassette toilet may have several guises inside the RV. It may be a modular unit, built onto the wall, with just a lid/seat and a lever or button to flush it. Or it may resemble a domestic toilet, freestanding and have a fixed or swivel bowl to make it easier to use in a smaller space. However, hidden beneath is where the magic happens.

The RV you’ve chosen with a cassette toilet will have an external hatch that reveals the cassette, and that’s what you have to prime for use and to empty when it’s full. Or preferably near or half full. You’ll know which is best for you the first time you pull a full cassette out of the chamber in terms of weight and manageability. Once out of the vehicle though, the cassette should have wheels and an extendable handle to wheel it to the dump point so you don’t have to carry it like a reluctant toddler as the contents swish from side to side. The dump point is a whole new world, as witnessed by many pictures of unfamiliar campers using them to wash-up, make coffee and fill water bottles. Gah! How about a kindly word of advice to those less informed than you and I, instead of framing their faux pas for social media. Or do both.

caravan toilet cleaning chemicals

The author’s stash of cleaning materials

Your cassette needs priming with water (and it will have a flush supply separate to the main chamber) and some form of chemical treatment adding. Now, the caravanning internet rages about what works and what doesn’t. You can use the dedicated products supplied by the toilet’s manufacturer or you can use nappy treatments and some people will even offer their own chemical recipes, freely on the internet for people to copy; less than ideal, in some cases. What’s paramount, however, is where it goes. Wherever possible, use a dedicated RV dump point because it’s what they’re for!

There’s no getting around the fact that tipping your own liquid waste into a hole the size of a saucer is not a spectator sport (it’s not much fun as a solo activity) but you will get used to it. I learnt something while writing this story that the green button atop a cassette is a breather that helps reduce splatter if you push it while pouring out. You’re welcome. Oh, And if an experienced camper tells you they’re ‘doing the honey run’, now you know what they mean.

For more than I can write to explain it, here’s a great video from Bryan Foster, at Fozzie’s Views on YouTube.


The downsides to using a cassette are that they can smell if you’re not up to scratch on chemical additives or maintenance on an older unit, but at least part of this can be remedied by adding an SOG system to remove odours. You can read how to install one here

A cassette system is not that easy to replace with another toilet set-up, and it does require you to be on top of the upkeep, and the what you have to do when it’s full routine. The upsides are it still has low water use, they’re widespread and available, you can carry a spare cassette, easy to clean and are available in right or left-hand configurations depending on your RV style. For a fancy cassette system with power supplied you can look at an installation like the Switch-Mode bathroom from Trakka Motorhomes. Watch a video here

Emptying a holding tank on an RV toilet

When the bottom falls out of the market

Gravity. Old-school thinking but still current! The inbuilt, gravity toilet system – can’t use the word fed in this context, it’s just wrong – means that your toilet takes the waste and down it goes into a holding tank. In turn, the tank needs emptying but is fixed in the RV. So, you need to move the whole rig to the dump point, meaning you kinda need to plan ahead. A large vehicle will limit access, and you have to hope that the dump point is positioned in such a way that you can manoeuvre your rig or the outflow pipe to a spot where gravity can actually do its job on your jobs effectively. Still, the waste is out of sight, this system is common, and it’s not expensive. Apart from the aforementioned negatives, the toilet must be positioned over the tanks, it can smell if you’re not on top of your treatments and it uses your water supply so that could be an issue for long-term free camping. Oh, and the system can block. Watch a video here

And worthy mentions

There are three more types that also use a holding tank but these set-ups don’t have to be positioned over the tank meaning designs can be changed to suit, if they’re on the drawing board. The macerator is kind of like a Nutribullet for your waste. Under electrical power, blades macerate the material before it enters a tank meaning an easier, liquid-like disposal. A vacuum flush toilet acts like an aeroplane loo taking the waste through a macerator again do the above task and add to the black water tank for disposal. A composting toilet is another option. Watch the video here to find out how they work.


Now you have the numbers on caravan toilets, you can see what your options are. I leave you with the video below. It’s the main reason I chose to write this story – to include this video. Camping toilet – Tuxman has the numbers.