Logo Thetford
man and woman sitting in front of camper van. Green grass and trees in the background. Two towels hanging to dry.

Cassette toilets remain the most sustainable choice for leisure vehicles

New comparison highlights the practical differences between bag welding and cassette toilet systems.

Home Inspiration Cassette toilets remain the most sustainable choice for leisure vehicles

With a growing number of innovative toilet systems being introduced to the leisure vehicle market, consumers and OEMs have more choice than ever. Thetford, a global leader in leisure vehicle sanitation, compared bag welding toilets and cassette toilets across key factors such as hygiene, discharge flexibility, environmental impact, and cost – offering clarity in a complex and evolving landscape.

Key insights

  • Hygiene handling: Waste of cassette toilets is safely stored in holding tanks, treated with additives, reducing exposure. Waste of bag welding toilets is stored in sealed, plastic foil bags.
  • Discharge flexibility: Cassette toilets can be emptied at widely available designated service points, into septic systems, or just in any toilet connected to a general sewage system or septic tank. Bag welding toilets require disposal of sealed plastic foil bags via the residual waste stream, which may face regulatory or logistical challenges.
  • Environmental impact: Cassette toilets require minimal plastic use and low energy. Thetford additives help break down waste, reduce gas-buildup and bad odours, and prepare the waste-holding tank for safely disposing at disposal points. Bag welding toilets operate without water but involve high single-use plastic bag consumption.
  • Cost advantage: Cassette toilets are up to 5x more cost-efficient in daily use. Bag welding toilets present higher recurring costs due to plastic foil bag use, energy, and a higher purchase price.

render bag welding toilet

Bag welding: simplicity with some trade-offs

Bag welding toilets offer an easy-to-use concept: waste is sealed in a sealed plastic foil bag and stored until disposal. The system requires minimal handling – users press a button to start the sealing process and need to clean the unit and empty the sealed bags once full. However, this convenience comes with logistical and environmental considerations. Waste bags end up in residual waste streams, where disposal and processing can be challenging depending on local infrastructure and regulations. Hygiene is compromised post-disposal if bags rupture in waste bins, waste compactors or landfill streams, posing environmental and health hazards, especially when liquid and solid waste are combined in one bag. Additionally, the required plastic consumption and energy usage raise valid questions about long-term sustainability.

Real-life scenario:

In a typical use case – two people using the toilet five times a day over three weeks – this amounts to 210 single-use plastic bags.

  • Running costs (three weeks): approx. €65.00 (€0.31 per bag)
  • Purchase price: typically €1,400–€1,500

Thetford C220 cassette toilet and holding tank

Cassette toilets: established, efficient and future-ready

Cassette toilets offer a long-standing, reliable solution to motorhome- and caravan users. Waste is collected in a sealed holding tank, treated with a few liters of water, and a dose of additives. Thetford additives reduce bad odours and gas build-up, and efficiently break down toilet waste for easier disposal.

The waste holding tank of the cassette toilet is mainly a temporary storage for toilet waste, which is later emptied into the sewage system to be treated safely. That is why toilet additives must be safe for wastewater treatment infrastructure, including sensitive ones like septic tanks – and all Thetford additives meet EU laws and regulations to ensure exactly that.

The tank is emptied at designated service points, which are widely available in Europe and in the United Kingdom, or at any toilet connected to a general sewage system or septic tank.

Compared to other toilet systems in the leisure vehicle industry, cassette toilets rely less on single-use materials and are designed for circular use. Additives and components, such as Fresh-up Set and Twusch, promote a more sustainable conscious way of travel.

Real-life scenario

For the same three-week, two-person use case:

  • Additive use (three weeks): less than one bottle of Aqua Kem® Blue Concentrated (11 doses = approx. €13.50)[1]
  • Water use: around 5% of typical household toilet use
  • Purchase price: Thetford C220 series: €639–€679

[1] Under normal use, 11 doses of Aqua Kem® Blue Concentrated can last up to 55 days. This comparison, however, is based on intensive use, assuming the tank is emptied every two days.

Thetford separation toilet

Looking ahead

As the sanitation market continues to evolve – with bag welding, separation and hybrid systems also emerging – it’s crucial to assess not just the user experience, but the full lifecycle of toilet systems. Dirk Valder, Manager Product Management RV/OEM, explains: ‘’We see a clear trend among a specific group of travellers who prefer to stay off-grid for extended periods. This group has different needs when it comes to sanitation, creating demand for alternative toilet systems tailored to their lifestyle. We take this development seriously and have therefore introduced both a separation toilet and a dedicated kit to support this way of travelling.

At the same time, the cassette toilet remains the most widely preferred option, not in the last place because the cassette toilet is designed to work with established sewage infrastructure, which continues to offer the most reliable and developed method of waste disposal.’

Thetford remains committed to driving responsible innovation, with solutions that meet both customer needs and environmental responsibilities.

Download the infographic

Choose your country