6 Best Waterless Urinals For Composting Toilet Setups

Managing human waste in a small space often comes down to one simple, non-negotiable rule: keep liquids and solids separate. While composting toilets handle the heavy lifting, adding a dedicated waterless urinal drastically extends the time between maintenance cycles. Mastering this transition transforms an odorous chore into a seamless, manageable part of off-grid living.

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Separett Privy 501: Best Urine-Diverting Seat

The Separett Privy 501 is the gold standard for those who want a discrete, high-quality solution without installing a full-blown commercial system. It functions as a simple drop-in seat that diverts urine away from the solid waste bucket immediately. By separating the streams at the source, it keeps the compost bin dry and significantly cuts down on the pungent ammonia odors typical of poorly managed setups.

This product is ideal for anyone retrofitting an existing bench or building a custom DIY toilet enclosure from scratch. Its design is intuitive, robust, and features a standard seat height that mimics a traditional household toilet, making it accessible for visitors who might be intimidated by more “rustic” options.

If you prioritize ease of installation and a clean, manufactured aesthetic, this is the definitive choice. It removes the guesswork from diversion geometry, ensuring you do not have to fiddle with custom plastic moldings or makeshift funnels. It is the perfect investment for a semi-permanent tiny home or stationary cabin.

Kildwick Klassik Diverter: Best for DIY Setups

The Kildwick Klassik is a precision-engineered urine diverter designed specifically for the hands-on builder. Unlike full toilet assemblies, this is a dedicated, ergonomic bowl meant to be integrated into a custom-built box. The contours are expertly shaped to catch fluid accurately while keeping the surrounding area dry, a feat that is surprisingly difficult to achieve with homemade designs.

Choose the Kildwick if you have the tools and the desire to build a custom-sized footprint. It is the best option for van conversions where every inch of floor space is at a premium and a full-size toilet chassis simply will not fit. Its high-quality, smooth finish is also significantly easier to clean than DIY resin or fiberglass alternatives.

This product is for the builder who values longevity over quick-fix solutions. While it requires more initial work to mount and plumb than a pre-fabricated unit, the result is a professional-grade station that will last for years. For those committed to the craft of custom living spaces, the Klassik provides the perfect foundation.

The Johnny-Pee Urinal: Purpose-Built for Vans

Space constraints in a van conversion often make a full-sized toilet system feel like an anchor. The Johnny-Pee is a compact, wall-mounted urine diverter specifically engineered for the tight quarters of a vehicle or small camper. It mounts securely to a wall or cabinet, allowing for a vertical orientation that keeps the floor clear for other activities.

This urinal is a lifesaver for long-term travelers who need a fast, spill-proof, and compact way to manage liquid waste without stopping to set up a composting unit. Because it utilizes a sealed bottle connection, it eliminates the need for complex plumbing or external tanks. It is essentially a “grab-and-go” solution for the nomadic lifestyle.

If you are a solo traveler or a couple living in a high-roof van, the Johnny-Pee is the most practical choice on the market. It sacrifices nothing in terms of space while solving the most frequent waste management problem on the road. Avoid this only if you require a traditional seat-based setup for comfort reasons.

Waterless Co. Baja Urinal: Most Residential Feel

Sometimes the goal is to replicate the comfort of a standard home bathroom in an off-grid cabin or accessory dwelling unit. The Waterless Co. Baja Urinal provides that familiar, high-capacity experience without using a drop of water. It is a large, wall-mounted fixture that looks and acts like a standard commercial urinal, but relies on a specialized trap system to manage odors.

This is the premier choice for stationary tiny homes or guest houses where space is not the primary constraint. It handles high-frequency use with ease and offers a level of hygiene and cleanliness that smaller, diverter-style systems cannot match. If you are building a home where multiple people reside, the Baja is the only way to ensure the bathroom feels like a proper, permanent facility.

The tradeoff here is the physical footprint. You will need a dedicated wall space and a robust mounting structure to support this unit. If you are living on the move, look elsewhere; if you are planting roots, this is the most sophisticated and durable option available.

Eco-Flow Waterless Urinal: Best Low-Profile Design

The Eco-Flow urinal stands out for its minimalist design and ease of installation in tight niches. It is essentially a sleek, low-profile basin that can be tucked into small bathroom corners or behind partition walls. It is a highly functional piece of hardware that emphasizes efficiency and speed in a high-traffic environment.

This unit excels in settings where you need a quick, no-fuss solution that remains largely out of sight. The installation is straightforward, typically involving a simple hose connection to a waste container or greywater tank. It is remarkably easy to wipe down and maintain, making it ideal for those who value low-maintenance infrastructure.

Consider the Eco-Flow if you are designing a compact bathroom and want a dedicated space for liquid waste that doesn’t feel like a piece of camping gear. It bridges the gap between commercial hardware and tiny-living utility, offering a refined, modern look for those who despise the “clunky” aesthetic of standard RV toilets.

DIY Funnel System: The Ultra-Budget Option

For the ultra-minimalist or those on a strict budget, a high-quality funnel coupled with a durable hose and a sealed jug is a functional starting point. Success here relies entirely on the quality of the seal and the orientation of the funnel. A wide-mouth, chemical-resistant funnel mounted into a customized seat or wall panel can be surprisingly effective if the plumbing is airtight.

This is the quintessential “fail-fast” method for temporary setups. If you are testing whether you even need a urinal before committing to a permanent fixture, start here. It is cheap, modular, and allows you to experiment with positioning before you commit to a permanent, expensive installation.

However, do not mistake a budget setup for a long-term solution. DIY funnels are often prone to splashing and are significantly harder to keep sanitized than purpose-built molded plastic or porcelain. Use this approach to gauge your needs, but plan to upgrade to a dedicated fixture within a few months of full-time living.

Why Add a Urinal to Your Composting Toilet?

The primary reason to separate urine is to stop the anaerobic process that creates the most offensive smells. A composting toilet relies on the decomposition of solids, which is hampered by excess moisture; when urine saturates the solid waste, it creates a “sludge” that is difficult to manage and incredibly foul. By diverting liquid, the solid waste stays dry, making it essentially odorless and much easier to compost or discard.

Adding a urinal also drastically increases the capacity of your waste system. Managing liquids separately means you are not emptying a heavy, liquid-filled bucket every two days. It allows you to focus solely on the solids, which only need to be addressed when the bin is actually full, often extending the maintenance interval from days to weeks.

Finally, a urinal improves the overall user experience. It provides a more convenient option for quick use during the night or when the main toilet is being serviced. For couples or small families in confined spaces, having a dedicated urinal prevents the main toilet from becoming a bottleneck, improving the flow of daily life.

Plumbing Your Urinal: To Tank or To Drain?

Deciding where the urine goes is the most critical technical step in your setup. If you are stationary, a dedicated greywater drain or a leach field (where local regulations permit) is the easiest path. This removes the need for manual transport and ensures that the liquid is processed far away from your living area.

For mobile setups, you must plumb to a portable, sealed holding tank. Always ensure this tank is opaque and features a secure, screw-top lid with a gasket to prevent sloshing and odor leaks. Placing the tank in a vented compartment or under the chassis is standard, but you must ensure the plumbing lines have a downward slope to prevent liquid from pooling in the hose, which can cause severe blockages.

Never allow your plumbing to stay exposed to direct sunlight, as UV rays will degrade plastic tubing over time, leading to brittle, leaking lines. Use high-quality, food-grade vinyl tubing or reinforced silicone hoses. Regardless of your chosen destination, prioritize airtight connections at every junction to maintain a sanitary environment.

Managing Odor: The Vinegar and Water Trick

Even with a well-plumbed system, urine can leave mineral deposits in the tubing that harbor bacteria and cause lingering smells. A simple, effective solution is a diluted vinegar and water flush. Running a mixture of one part white vinegar to three parts water through the urinal after each use or at the end of the day dissolves the salts and neutralizes the ammonia smell instantly.

Avoid using harsh commercial bathroom cleaners, as they can damage the specialized traps in waterless urinals or degrade the seals on your holding tanks. Vinegar is mild, cost-effective, and safe for most composting environments. If you find the smell persists, it usually indicates a lack of proper venting rather than a failure of the liquid system itself.

Always consider adding a carbon filter to your vent line if the smell becomes an issue in hot weather. A small, inline PC fan installed in the vent pipe to create a constant negative pressure draft is the most effective way to ensure no odors enter your living space. This small addition makes a massive difference in comfort.

Dealing With Urine: Storage and Disposal Guide

Handling human waste is a reality of off-grid life that requires a strict protocol. For urine, ensure you have multiple sealed containers rather than one giant tank; carrying a single 20-gallon tank is physically impossible in many settings, while two 5-gallon jugs are manageable and easy to swap out. Always use containers labeled specifically for “non-potable” use to avoid accidental ingestion.

Disposal depends entirely on your local site rules. If you are on private land, you can often dilute and disperse urine in a designated area away from water sources, as it is high in nitrogen and acts as a fertilizer for non-edible plants. If you are in a park or an urban setting, you must use public dump stations or municipal sewer connections.

Consistency is key to keeping the process manageable. Never let your storage containers reach total capacity before emptying them, as the risk of spills increases significantly when a container is full. Establishing a weekly “waste day” keeps the process routine and prevents the stress of managing a full tank during unexpected situations.

Investing in a waterless urinal is one of the most effective ways to upgrade the quality of life in any small-space setup. By focusing on moisture control and selecting the right hardware for your mobility needs, you eliminate the biggest pain point of alternative living. Choose the option that fits your long-term setup, maintain your plumbing lines, and you will find that managing waste is no longer a chore, but a simple, automated part of your routine.