When it comes to travelling off-grid in a caravan, waste management is a big consideration. While traditional cassette toilets are common, many travellers are now switching to composting toilets for their simplicity, sustainability, and odour-free operation.
But how do they actually work in a caravan setting? What makes them different from chemical toilets or regular RV setups? And most importantly, are they worth the investment for long-term travellers or weekend warriors?
If you’re exploring caravans in Heatherbrae and thinking about how to stay self-contained and eco-conscious on the road, this guide is for you.
Let’s break down how a composting toilet functions, what it requires, and why more Australians are making the switch.
The Core Concept: Separating Liquids from Solids
The key to a composting toilet’s success lies in its waste separation system. Unlike chemical toilets that combine everything into one tank, a composting unit keeps liquid (urine) and solid (faeces) waste in separate compartments.
Here’s why that matters:
- Mixing waste causes strong odours
- Urine is mostly sterile and easy to manage
- Solids can be dried and composted safely
By splitting waste, composting toilets avoid the nasty smells and chemical treatments associated with traditional setups. This is especially useful in confined caravan spaces.
The toilet has two chambers:
- A front chamber or funnel for urine
- A rear container or bin for solids, often lined with compostable material
This separation starts the composting process naturally and keeps things cleaner and easier to manage.
Composting Solids: What Actually Happens?
Once solids are deposited into the rear chamber, they’re covered with a carbon-based material like:
- Coconut coir
- Peat moss
- Sawdust
This cover material helps absorb moisture, promote airflow, and kickstart the breakdown of waste. Most systems include a manual agitator or stirrer, which you turn after each use to mix the waste with the composting medium.
Here’s what happens next:
- Moisture evaporates, helped by ventilation fans
- Bacteria break down the waste over time
- The result is dry, inoffensive material that resembles mulch
Depending on use and temperature, the composting process can take several weeks to complete. However, most caravan toilets simply act as a holding system—you empty the contents into a compost bin or green waste system every few weeks rather than waiting for full composting.
Managing Liquids: How Urine is Handled
Urine is collected separately and typically directed into a removable front tank. Since urine doesn’t need to be composted, you can empty this tank more frequently—usually every 2–3 days depending on usage.
Some composting toilets have diverter hoses to drain urine outside the van (where permitted), but most use a tank that’s emptied into:
- A household toilet
- A greywater disposal area
- An approved dump point
The key with urine is frequent emptying. Leaving it too long can cause odours or overflow. Fortunately, it’s a quick and simple process, and there are no chemicals involved.
Power and Ventilation Requirements
One of the essential components of a caravan composting toilet is the ventilation system. This usually involves:
- A small 12V fan
- A vent pipe directed outside the van
- Airflow to remove moisture and odours
The fan draws air from the solids chamber, helping dry the waste and push smells outside. It uses minimal power—roughly the same as a computer fan—so it’s ideal for off-grid setups with solar.
If the fan fails or isn’t used, composting slows down and odours may become noticeable. That’s why a consistent power supply (even just a battery bank) is helpful to keep things running smoothly.
Maintenance and Emptying: How Often and How Messy?
The idea of emptying a composting toilet can turn some people off, but the reality is surprisingly simple.
Here’s a typical maintenance timeline:
- Liquids tank: Every 2–3 days
- Solids chamber: Every 2–3 weeks for two people full-time
When it’s time to empty the solids, you simply unclip the chamber, tip it into a compost bin or large garbage bag, and rinse. Because the waste is dry and partially broken down, there’s usually no strong smell or visible mess.
The biggest difference? No harsh chemicals, no blue liquids, and no dump points required—just natural breakdown and a bit of elbow grease.
Benefits of Composting Toilets in Caravans
Why are more Aussie travellers making the switch? Here’s a quick breakdown of the perks:
- Odourless when maintained properly
- No need for chemicals or expensive treatments
- Saves water, which is critical when off-grid
- Lower environmental impact
- Fewer trips to dump points
- Longer time off-grid without services
They’re especially popular among full-timers, grey nomads, and anyone doing extended off-grid touring. If you’re relying on solar and rainwater, composting toilets are a natural fit.
Are There Any Downsides?
Like any system, composting toilets come with a few trade-offs:
- Initial cost is higher than a cassette toilet
- Learning curve for maintenance and emptying
- Space needed for ventilation and airflow
- Regulations around waste disposal (especially for solids)
Some travellers find the process fiddly at first, particularly with liquids. But with a routine and a bit of practice, it quickly becomes second nature.
Can You Install One in Any Caravan?
Most modern composting toilets are compact enough to fit in standard caravan bathrooms. That said, you’ll need to:
- Allow room for the unit and ventilation pipe
- Run a 12V line for the fan
- Have access for emptying chambers
Popular models like Nature’s Head, AirHead, and Simploo are designed for small spaces and come with flexible install options.
If your caravan already has a cassette setup, you may need to modify the bathroom area to accommodate the venting and urine tank. But many vanlifers find the upgrade well worth it—especially when they can stay off-grid longer.
Environmental Impact: Why It Matters
Traditional caravan toilets rely on chemicals and frequent dumping—often into treatment plants or septic systems. This uses water, energy, and generates pollution.
Composting toilets offer a closed-loop alternative. They turn waste into compost, reduce water usage, and avoid adding chemicals into natural ecosystems.
For eco-conscious travellers or anyone looking to tread lightly, it’s a step in the right direction. Plus, there’s something rewarding about turning your waste into something harmless and natural.
FAQs
Do composting toilets smell in caravans?
Not if they’re maintained correctly. The combination of waste separation, dry composting material, and a ventilation fan ensures that odours are either eliminated or vented outside.
Most users report no smell inside the van—even when emptying the solids chamber. If smells do occur, they’re usually a sign that the fan isn’t working, the unit is too moist, or the carbon material needs replenishing.
How often do you empty a caravan composting toilet?
For two full-time users, the solids chamber usually needs emptying every 2–3 weeks. The liquids tank is more frequent—every 2–3 days is typical.
Frequency can vary depending on the size of your tanks, number of users, and whether you’re using it full-time or occasionally. Keeping a regular schedule makes it manageable and keeps everything odour-free and efficient.
Can composting toilets go in all caravan types?
Yes, with the right space and airflow. Most composting toilets are compact and designed for mobile living. They can be retrofitted into caravans, motorhomes, and even vans or tiny homes.
However, you’ll need to account for:
- Ventilation (usually through the wall or floor)
- 12V power for the fan
- Clearance to remove the liquids bottle or solids chamber
If you’re converting an older van or doing a custom build, it’s worth designing your bathroom around the unit from the start.
Do I need chemicals or special products?
No chemicals are needed for composting toilets. Instead, you’ll use a natural carbon-based medium like coconut coir or sawdust to help break down solids.
This approach is not only more eco-friendly, it’s also cheaper in the long run. You don’t need to buy blue additives, deodorising tablets, or waste tank treatments—just natural materials and a basic cleaning routine.
Is it legal to compost toilet waste in Australia?
Yes, but with conditions. You can compost your toilet waste, provided it’s done responsibly and in accordance with local council regulations.
Solid waste should be disposed of in:
- A dedicated composting bin
- An authorised green waste system
- A legal disposal site
Urine can usually be poured into a toilet or greywater outlet. Avoid dumping in natural areas or storm drains. Always check the rules in your region—especially if you plan to dispose of waste on private or public land.
Off-Grid Ready, Eco-Friendly, and Surprisingly Simple
A composting toilet isn’t just a trendy upgrade—it’s a practical, efficient way to manage waste on the road. Once you get the hang of it, you’ll wonder why you ever put up with chemicals and dump stations.
If you’re planning long trips, off-grid adventures or simply want a cleaner footprint, it’s worth exploring your options. With the right setup, your van can be self-contained, sustainable, and smell-free.
Start your journey with confidence — visit 7th Street Caravans or give our team a call on 02 4012 6009 for friendly, local advice.