Frequently Asked Questions (FAQs)

No. A composting toilet is a managed waterless toilet system designed to process waste in a controlled chamber with ventilation and the right operating conditions. A long drop is simply a pit arrangement and is not the same technology.

Properly installed composting toilets should not smell in the room. Most systems rely on continuous venting to pull air through the toilet and out above the building.

If odour is present, it usually points to a ventilation, moisture, or operating issue rather than the toilet concept itself.

Usually not in split-system models, because the chamber sits below the floor or away from the bathroom space. In self-contained models, visibility varies by chamber design and screen arrangement.

Usually no. Standard toilet paper is generally suitable, provided it is normal toilet tissue and not a wipe or heavily reinforced product.

Avoid wet wipes and similar products, even if they are marketed as flushable.

Yes, but use suitable cleaners. The toilet pedestal and bathroom surfaces can still be cleaned normally, but harsh chemicals should be avoided where they may interfere with the composting process.

Use mild, suitable cleaners rather than harsh bleach, caustic products, or strong antibacterial chemicals. Where possible, use products intended for composting toilet systems.

For a fuller explanation of safe cleaning products and treatment additives, see Approved Cleaning & Treatment Products.

WCTNZ® also offers Nature Flush enzyme products for compatible cleaning and system care.

• Nature Flush | Enzyme 750ml Trigger Pack
• Nature Flush | Enzymes - 1 Litre Concentrate
• Nature Flush | Enzymes - 5 Litre Concentrate

Yes, a small amount of water from routine cleaning is usually fine. What should be avoided is regularly soaking the chamber or introducing unnecessary liquid loads.

For most people, it becomes normal very quickly. Day-to-day use is usually simple: use the toilet as intended, then add bulking agent where the system requires it.

Usually yes. A short sign or quick explanation is often enough, especially for first-time visitors. Most systems are easy to use once guests know there is no flush and bulking material may need to be added.

Use dry, carbon-rich bulking materials that suit your system, such as untreated wood shavings, coco coir, peat-based material where appropriate, or other approved dry compost bulking media.

Avoid materials that are too wet, too fine, chemically treated, or likely to mat together.

The correct bulking material and dosing class are system-specific. For more detail, see Bulking Agents & Dosing Guide.

Usually no. A healthy composting toilet normally develops the biology it needs through normal use and the right operating conditions.

If the system has been upset by unsuitable chemicals or difficult conditions, a recovery or starter product may sometimes help.

Avoid anything that does not belong in a composting toilet system, including wipes, nappies, sanitary products, cigarette butts, food scraps, mop water, and harsh chemical cleaners.

That is not recommended. Wet wipes, sanitary items, and similar products do not break down properly and can create servicing problems.

Generally no. Composting toilets are designed for human waste, toilet paper, and approved bulking material. Food scraps can attract pests, and worms are not a standard requirement for these systems.

It depends on the system type, chamber size, and level of use. Some lightly used systems may go long periods between emptying, while higher-use systems may need more regular removal.

The right answer is always system-specific.

Unexpected odour usually means something needs checking. Common causes include poor airflow, a fan or vent issue, too much moisture, unsuitable inputs, or a chamber condition that needs correction.

Start with ventilation, moisture balance, and bulking material, then contact WCTNZ® if needed.

For ventilation-related guidance, see Passive Ventilation Design Parameters Guide and Room Ventilation and Extraction Systems Guide.

Yes. Many composting toilets are well suited to seasonal properties such as baches or occasional-use buildings. On return, the system may simply need a quick check, fresh bulking material, and normal recommissioning.

Yes. Composting toilet systems are available for very light use through to larger residential and commercial applications. Matching the system to the occupancy and use pattern is important.

They can be straightforward when properly planned, but installation still needs to suit the specific model and site. Some systems are simpler than others, while split-systems may require more layout planning.

Professional installation is often the safest path.

That depends on the product, the site, and the project pathway. Product certification and supporting documents can help, but final approval still depends on the actual application and the authority involved.

For more guidance, see Certified Technology and Advice on the Consent Process.

Yes. Composting toilets are often well suited to off-grid projects because they reduce water demand and can simplify blackwater handling. Some models require only low power for fan ventilation, while others may require more.

It depends on the system. Self-contained models may fit within a standard bathroom footprint, while split-systems need space for the remote or underfloor composting chamber.

Some systems are much easier to relocate than others. Self-contained units are generally more portable, while split-systems usually require more work to remove and reinstall.

With correct installation, normal care, and access to replacement parts where needed, composting toilets can provide long service lives. Supporting components such as fans may need replacement before the main system does.

Handling guidance depends on the system and the stage of the material. Some systems require a secondary maturation period before final use or disposal. Follow the product guidance and use sensible hygiene precautions when handling any composted material.

Usually much less than people expect. Volume reduces significantly during the process, so the final material is a fraction of the original waste volume.

That depends on the system, the maturity of the material, and the applicable local requirements. A cautious approach is to use fully matured material around non-edible landscaping or tree planting rather than on edible crops.

When properly processed and matured, the final material is usually dark, crumbly, and soil-like rather than recognisable waste.

A composting toilet uses no flush water, so the water saving can be substantial over time compared with conventional toilets. The actual savings depend on the household size and what type of flushing toilet it replaces.

People choose composting toilets to save water, reduce blackwater infrastructure, support off-grid or low-impact living, and build more resilient wastewater solutions for sites where conventional sewer or septic arrangements are not ideal.

A desiccating toilet is a waterless toilet designed to dry waste rather than rely on full composting inside the chamber. The goal is moisture reduction and stabilisation rather than active compost production in the same way as a true composting toilet.

A composting toilet is designed around biological breakdown under the right moisture, airflow, and carbon conditions. A desiccating toilet is designed to dry the material out.

Both are waterless technologies, but they work differently and should not be treated as the same system type.

Not in the same sense as a true composting toilet. The output is usually dried and stabilised material rather than finished compost.

That depends on the design. Many desiccating toilets separate urine and direct it to a collection point or external drainage pathway, because keeping solids dry is a key part of how the system works.

It is usually lighter, drier, and more reduced in volume than fresh waste, but it should not automatically be described as finished compost.

They can be, especially where waterless operation and compact form are important. The right answer depends on use levels, expected maintenance, and how the residual material will be managed.

Often yes. Desiccating toilets are commonly better suited to lower or intermittent use than heavy, continuous use.

They often suit seasonal use well because dry systems can be practical for occasional-occupancy buildings, provided the system is chosen and maintained correctly.

They are often most suitable for lighter-use, intermittent, or space-conscious projects where a simple dry toilet pathway is preferred over a full composting or flush-based setup.

Some do and some do not. It depends on whether the model uses fans, heaters, or other assisted drying components.

Many models use a fan, heater, or both to help remove moisture and support drying. The exact requirement depends on the product design.

Properly installed dry toilets should not smell in the room. If odour is present, it usually points to a ventilation, drainage, or maintenance issue.

That depends on the chamber size, the model, and the level of use. Lower-use systems may go much longer between servicing than higher-use systems.

Human waste, normal toilet paper, and any approved cover material specified by the manufacturer are usually acceptable. Always follow the model-specific guidance.

Wipes, sanitary items, food scraps, strong chemicals, and anything not intended for a dry toilet system should be kept out.

They can be straightforward, but they are still an active system and need the right use habits, emptying routine, and general care.

That depends on the system, the condition of the material, and the local requirements. A cautious, product-specific approach is the right one.

Desiccating toilets generally avoid the same reliance on liquid chemical waste storage, but they still require proper servicing and residual material handling. They are a different pathway, not just a different container.

Composting toilets are aimed at managed biological breakdown. Desiccating toilets are aimed at drying. Which is better depends on the site, expected use, and what management pathway the owner prefers.

That depends on the product, the site, and the project pathway. Approval is never just about the name of the technology.

An incinerating toilet is a toilet that reduces waste to ash using heat rather than water or composting. It is a very different technology from both composting and desiccating systems.

The toilet collects waste in a chamber or burn zone and uses a controlled heat cycle to reduce it to a small quantity of ash. Different models do this in different ways, but heat is the core process.

During a burn cycle, the unit applies heat to reduce waste volume and leave ash behind. Cycle time varies by model and by how the toilet is used.

Usually very little compared with the original waste volume. One of the main features of incinerating toilets is how much the final residual volume is reduced.

That depends on the model. Some incinerating toilets are electric, while others use gas or another fuel source.

Yes. They differ in installation requirements, energy source, running profile, and often where they are best suited.

Running costs are an important consideration with incinerating toilets and are generally higher than many people first expect. Energy or fuel use can be significant, so they are not usually chosen because they are cheap to operate.

Often yes. Composting toilets usually have lower ongoing energy demand, while incinerating toilets rely on repeated heat cycles.

Some can, but only where the site can realistically support the required power or fuel demand. They are not automatically the best off-grid option just because they are waterless.

Inside the room they should be managed properly if installed correctly, but exhaust design and ventilation still matter. Like any specialist toilet system, performance depends heavily on correct installation and use.

Yes. Incinerating toilets require proper venting or exhaust arrangements in line with the model requirements.

Some models produce noticeable fan or operating noise. Noise level varies by unit and installation.

Usually yes, once basic instructions are given. They are still less familiar than a standard flushing toilet, so simple guidance helps.

That depends on the model and level of use, but usually much less frequently than people expect because the remaining ash volume is small.

Maintenance usually includes ash removal, internal cleaning, inspection of vents or exhaust components, and routine servicing in line with the manufacturer’s guidance.

They can be, but they are usually chosen for specific reasons such as limited water, difficult infrastructure, or preference for ash handling over compost handling. They are not the default best option for every home.

Sometimes, but only if the power or fuel supply is realistic and ongoing running cost is acceptable. Remote does not automatically mean incinerating is the best fit.

That depends entirely on the model. Heavy use places real demand on any incinerating system, so the product specification matters.

The main advantages are waterless operation, very low residual waste volume, and no compost chamber management. For the right site, those can be useful strengths.

It is often the wrong choice where energy use, fuel supply, operating cost, or long-cycle practicality do not suit the project. They are a specialist option, not a universal solution.

Greywater is household wastewater that has not come into direct contact with toilet waste. In practical terms, it commonly includes wastewater from showers, baths, basins, laundries, and, in broader wastewater classification, kitchen wastewater as well.

Yes. WCTNZ® does not treat kitchen wastewater as blackwater. It remains greywater by category, but it is usually one of the higher-strength greywater sources and often needs more careful design.

Greywater is wastewater from non-toilet household sources. Blackwater is wastewater that contains toilet waste. That difference matters because the handling, treatment, and reuse pathways are not the same.

Kitchen greywater often carries more grease, oil, food solids, and organic loading than lighter bathroom greywater. That does not change its category, but it does make it more demanding in practical design.

A GWDD is a diversion-based pathway used where suitable greywater is directed promptly to an appropriate discharge arrangement. A GTS is a treatment-based pathway used where greater water quality improvement and more controlled reuse or discharge are needed.

A DGTS is a Domestic Greywater Treatment System. It is intended for residential or lighter-use projects where treatment is required rather than simple diversion.

A CGTS is a Commercial Greywater Treatment System. It is intended for larger-scale or higher-use projects where the wastewater load and project demands are greater.

Diversion is about moving suitable greywater quickly to the right discharge arrangement. Treatment is about improving water quality first so the project can support more controlled reuse or discharge outcomes.

Yes, where the project, wastewater source, and discharge arrangement are suitable. The right reuse outcome depends on both the water source and the technology pathway.

Subsurface application is generally more controlled, less exposed, and better suited to wastewater reuse than open surface discharge.

Not always, but dripper systems usually provide a more even and controlled distribution pattern. For more refined projects, that can be a major advantage.

Yes, but the system needs to be designed appropriately for it. Kitchen wastewater should not be treated casually just because it is still greywater.

No. Kitchen wastewater does not automatically force every project into a treatment system, but it usually increases the need for more careful design and may make treatment the better pathway.

Not casually, and generally not for long periods without proper design. Greywater quality can deteriorate quickly when left standing.

When greywater sits, odour can develop, solids can settle, biological activity changes, and the water becomes less desirable to handle. That is why prompt diversion or proper treatment design matters.

Some do and some do not. If gravity fall is sufficient, a pump may not be needed. If the layout requires lifting or staged transfer, pumping may become part of the design.

A surge tank helps manage short-term inflow and can support transfer, filtration, or discharge control within the wider greywater layout.

They help protect downstream components by screening solids and improving flow quality before discharge, irrigation, or further handling.

That depends on the filter type, wastewater source, and level of use. Higher-strength greywater usually means more maintenance attention.

Yes. In many projects, composting toilets and greywater systems are a logical pairing because they separate blackwater reduction from greywater management.

Yes. A composting toilet reduces or changes blackwater handling, but your greywater still needs its own suitable discharge or treatment pathway.

Yes, but the right solution depends on water source, occupancy, kitchen inclusion, and available discharge area. Tiny does not always mean simple.

Yes. Larger homes often need a more developed and better-controlled greywater response because the loading is greater.

Project scale, usage intensity, shared or public use, and the required system response all help determine whether the project should be treated as commercial.

Start with the wastewater sources, the level of use, whether kitchen wastewater is included, the intended reuse or discharge outcome, and the site conditions. Those factors usually determine the right pathway.

A grease trap is a device used to separate fats, oils, and grease from wastewater before they move further downstream into drainage or treatment infrastructure.

You may need one to protect drains, greywater systems, septic systems, or treatment infrastructure from grease-related loading and blockage problems.

No. They are more common in commercial settings, but some residential or mixed-use projects can also benefit from grease interception.

Yes. Pre-treating kitchen wastewater can help protect downstream greywater infrastructure from fats, oils, and food solids.

Yes. Reducing grease load before wastewater enters the broader system can help reduce stress on downstream components.

They can help significantly where fats, oils, and grease are a major cause of downstream drain problems.

That depends on the application, flow, fixture load, and expected grease loading. Sizing should be matched to the actual use case, not guessed.

It should be installed where it can intercept relevant wastewater before it reaches the downstream drainage or treatment pathway, while still remaining accessible for servicing.

Yes. That is one of the main reasons grease traps are used in the first place.

Sometimes yes, especially where the downstream system is sensitive or where kitchen wastewater needs more careful management.

Yes, some commercial projects require grease management as part of the broader wastewater arrangement. The exact requirement depends on the project and the authority involved.

That depends on the size of the trap, what is entering it, and how heavily it is used. Higher grease loading means more frequent servicing.

Poor maintenance can lead to odour, blockage, carryover of grease downstream, and reduced system performance.

They can help when grease accumulation is part of the odour problem, but they are not a cure-all if maintenance is poor.

Passive systems rely mainly on separation by flow conditions and retention. Active systems use additional mechanical or managed processes to improve grease handling.

Not always. Additives may support a maintenance strategy in some cases, but they do not replace correct sizing, installation, and cleaning.

They can have a place, but they should be seen as support products rather than a substitute for proper trap management.

Kitchen wastewater may go through the trap, but it should not be treated as a disposal point for solids, wipes, or inappropriate waste streams.

That depends on the model, but seals, baskets, internal components, and serviceable accessories may require replacement over time.

If the current trap is undersized, hard to service, underperforming, or no longer suits the site demand, an upgrade may be the better option.

A pump station is a transfer system used where gravity flow is not enough and wastewater or water needs to be lifted or moved to the next stage of the layout.

You need one when the site layout, depth, fall, or discharge point means gravity drainage alone is not enough.

If the site cannot achieve the required fall to the destination point, pumping may be needed. This is usually confirmed during design or installation planning.

A sewage macerator system is designed to handle solids by breaking them down before pumping. An effluent pump station is typically intended for more settled or screened wastewater and not the same solids load.

They are designed for different water types and site demands. Stormwater systems are aimed at rain and runoff transfer, while drainage systems can be aimed at site water or groundwater-related collection.

Yes, where the pump station is suitable for that wastewater type and the wider layout calls for lifting or staged transfer.

Yes, but only if it is designed for that duty. Blackwater pump handling is not the same as simple water transfer.

A macerator breaks solids down so they can be pumped through the system. It is used where the wastewater stream and pipework arrangement call for that kind of handling.

That depends on inflow rate, storage volume, pump duty, wastewater type, and the discharge requirements. Correct sizing is a design question, not just a product guess.

Storage volume is how much liquid the station can hold. Pump capacity is how quickly the station can move that liquid when required.

Yes. Many pump stations are used on residential sites where gravity fall is not available or where the layout needs staged transfer.

Yes. Commercial projects often rely on pump stations where flow conditions, layout, or infrastructure demand them.

Yes, many are designed specifically for underground installation, provided the site and installation method suit the product.

Start with the water type, solids load, flow rate, discharge point, and site conditions. Those factors usually determine the right pump category.

If power fails, the station cannot pump until supply is restored unless the system has backup provision. Storage capacity and alarms become especially important in that situation.

Many do, and alarm provision is an important part of pump station risk management.

When installed correctly, they are usually not obtrusive in normal use, though some noise during cycling is expected depending on the equipment type and location.

They need routine inspection, cleaning where relevant, alarm checks, and service attention in line with the duty and product type.

That depends on the type of station, how heavily it is used, and the criticality of the application. Higher-duty or commercial systems usually justify more regular servicing.

That varies by station, but pumps, float switches, alarms, control components, seals, and serviceable accessories are common maintenance items.

A waterfree urinal is a urinal designed to operate without flush water. It uses a cartridge, trap liquid, membrane, or other odour-control method depending on the system type.

It allows urine to pass through while controlling odour from the waste line below. Different products achieve that in different ways, but the goal is the same: waterless operation with odour control.

They should not smell when the correct consumables, cartridges, or maintenance procedures are followed. Odour usually points to servicing, installation, or product-care issues.

That depends on the design. Some use cartridges, some use sealing liquids, and some use other service media or replaceable internal components.

It depends on the product and level of use. High-use public or commercial settings usually require more frequent servicing than low-use private sites.

Yes. Eliminating flush water can create substantial savings over time, especially in higher-use settings.

No, but they do require the correct consumables and servicing routine. They are not maintenance-free just because they do not use water.

Use cleaning products suitable for the urinal system and avoid anything that can damage cartridges, membranes, or odour-control media.

Cartridges, trap components, seals, media, and some serviceable internal parts may need replacement over time depending on the system.

Common causes include overdue consumable replacement, unsuitable cleaning chemicals, installation issues, or lack of correct maintenance.

That depends on the product line, but access to the right support parts is an important consideration when choosing a waterfree urinal system.

They can be, though they are more commonly used in commercial or shared-use settings where the water-saving value is more obvious.

Often yes. Commercial, public, and shared-use projects usually gain the most from waterfree urinal technology.

Yes, provided the product and maintenance pathway are suitable for the level of use and the facility requirements.

They often are, especially where water saving, servicing simplicity, and reduced flush infrastructure are important.

Yes. In the right project, they can form part of a wider water-efficiency and infrastructure-reduction strategy.

Start with the use case: home, public, shared-use, premium fitout, or low-infrastructure site. From there, servicing expectations and water-saving goals usually help narrow the right option.

A waterless pedestal is only one fixture component within a broader system. A composting toilet pedestal is part of a composting toilet arrangement designed to work with a composting chamber and its specific airflow and waste pathway.

A microflush toilet uses a very small amount of water per use rather than operating completely waterless. It sits between conventional flush toilets and fully waterless toilet technologies.

A microflush toilet may suit projects that still want a flush-like user experience with much lower water demand, while a full composting system is a more fully waterless pathway.