Let’s talk about the topic we don’t like to discuss but we all need when travelling – the loo.

When free camping or staying somewhere that has no public toilets, this essential facility is as important as the availability of drinking water as it limits how long we can stay at a particular campsite. When planning our trip, we wanted to be able to free camp for periods of at least a week, so we bought a second Thetford toilet cassette. I mounted a box on the rear of the caravan to carry it and the toilet chemicals and we were glad we had it available more than a few times.

A common question asked on social media is, what chemicals to use in them? Seems to be a very contentious topic so I’ll try to dispel a few myths.

The first one is often quoted – nappy and laundry products will wreck septic tank systems. Thirty years ago this was true because the active ingredient of Napisan was potassium monopersulfate. The cause of the damage was because this compound oxidises sodium chloride into sodium hypochlorite – ie: bleach. My understanding is this kills the ‘good’ bacteria that breaks down human waste.

Since then, the popular well-known brand and others contain sodium percarbonate in varying quantities depending on the brand. When that active ingredient is dissolved in water, it forms sodium carbonate and hydrogen peroxide. It is the last ingredient that oxidises smelly compounds – including, you guessed it, number twos. So that’s the first myth and in fact, using these much cheaper chemicals are fine in cassette toilets and don’t damage septic tank systems.

Myth number two (sorry couldn’t help myself there) is that caravan and motorhome toilets are always smelly.

They can be but they don’t have to be. Regular, thorough cleaning is an important way to avoid smells – take your time when emptying the cassette, use plenty of water to flush everything out. Put the correct amount of chemicals in (mix well with water in the case of laundry products) straightaway before replacing in the toilet hatch. Use a small quantity of oil on the rubber seals to ensure they don’t dry out and become brittle. I use a small spray bottle of cheap olive oil. Old timers swear that a half a capful of eucalyptus oil in the cassette stops smells too but we didn’t try this out. We did find that topping up the toilet with a capful of the laundry product after a few days of daily use helped the most to prevent any smells.

Be careful of using normal toilet cleaning products or putting any chemicals in the flush tank too. Always use products that state they are safe for septic systems – we find that white vinegar is an excellent natural cleaning product that has many uses in the caravan and around the home.

Toilet ventilation systems have been on the market for a while now and users of these systems say they are an excellent method to stop smells and apparently chemicals are not needed with them. I have no experience with these but they certainly look like a clever idea and use very little 12V power.

Portable toilets are no different to the inbuilt cassette toilets as far as cleaning and maintaining and are popular with those campers without permanent toilets – we use one in a privacy tent whenever we are camping somewhere without facilities.

Composting toilets are becoming a popular alternative to cassette style models. Again, I don’t have personal experience but there are plenty of videos on YouTube about them and I think if we were ever to live full time in a motorhome or caravan, this would be a good solution.

I hope this post has provided some useful information, especially to those new to caravan or motorhome travelling.

More Info : Which laundry brands are best in cassette toilets?
Brands containing more than 300 g/kg of sodium percarbonate are best, so check the labels carefully before buying and look for a statement ‘safe for septic tanks’ – we found that the home brand varieties were higher in the active ingredient than the some of the other well known brands