Commonly Asked Composting Toilet Questions & Answers

Commonly Asked Composting Toilet Questions & Answers

The Q & A below are the most Frequently Asked Questions (FAQ) we are asked about MullToa / Biolet Composting Toilets. 

MullToa Composting Toilet

What is a closed system? Is it the same as a self-contained composting toilet?
They are not the same. A closed system has no water in and no drain or “overflow” out. A self-contained system (somewhat misleading if you ask us) refers to units that are located above the floor. Many of these units have an “overflow” drain tube to be attached.

Is there a manual drum to turn? Or levers to wiggle or sift?
No. The Mulltoa 65, MullToa 55 and MullToa 25 are all fully automatic units. Closing the toilet seat lid activates the mixing motor for you.

Does the bowl/trap open and close automatically?
Yes automatically. Sitting on the seat triggers the compost covers to automatically open.

Does a male use the system while standing?

Yes. The MullToa 65 and 55 both include the latest in seat technology. The compost covers conceal toilet contents from view, however sit or lift the toilet seat and they move out of the way for use as per a “regular toilet”.

Do any of the units have a step or step up?
No step or step up. They have a convenient toilet seat height of 52cm (approx 20.5 inches) from the floor.

Are the toilets tested?
Yes, CSA/Intertek certified PLUS the MullToa 65 is Eco Certified (Nordic Ecolabelling, Svan Mark), the only waterless composting toilet with this certification in North America.

What is Nordic EcoLabelling, Svan Mark certification?
The Nordic EcoLabelling program has the strictest criteria for composting toilets in the world. This extensive testing requires a closed toilet system to be “a toilet that is not connected to a drainage system for receiving faeces and urine”. Without a drain, the toilet must handle waste from four people in a permanent use situation (with no drain installed), and the end product must be safe and utilized as a means of soil improvement.
Additional information can be found at: 

Do I need a permit to install a MullToa Toilet?
No, this is a closed system with no drain or water connection.

No Drain, really? Where does the urine go?
That is right. The MullToa 65, MullToa 55 and MullToa 25 all are without a drain or “overflow” (which is a drain by another name and requires a municipal permit in many areas of Canada). With MullToa Composting Toilets the “solid” contributions are composted and liquids are evaporated. More indepth information can be found at How they work?

Is the compost safe to handle? And what do I do with the finished compost?
Yes, the MullToa 65 was tested and verified by independent laboratory at the University of Norway, there are less than 2 fecal coli form bacteria and 0 E.coli per dry weight gram of finished compost (humus) from a MullToa toilet. Either mix it 30:1 with garden soil and apply to a flower bed or you can put it into your backyard composter to later be used around trees and shrubs.

How often do need to empty the humus tray?
Depending on use, the tray is emptied every few months, for seasonal use once a year is usually enough. Heavier use will require emptying more frequently.

Do I need to add humus or mulch or something to a MullToa?
Yes only MullToa Mulch. MullToa Mulch is unique mix of media necessary for proper composting in the MullToa units. It will not damage any internal components or mechanisms. Two 30L bags come with each unit and additional 30L bags are $36 per bag. Most MullToa unit owners require one or two bags a year maximum.

What about Microbe Accelerators? Do I need this too?
No. Microbe accelerators are not needed. The MullToa’s intelligent design and patented system takes care of the composting process. No boosters are needed.

How do I clean my MullToa Toilet?
Use a non-toxic, biodegradable cleanser on a soft cloth or sponge to clean the MullToa. Due to the unique nature of the “Bowl” area of the MullToa, there is little chance of waste coming into contact with the visible areas of the toilet.

Do I need to use special toilet paper in the MullToa?
Pretty much any toilet paper can be used. We do not recommend “reinforced” types.

How much electricity does the toilet use?
On average, under full time use, the toilet uses 4 - 6 kWh per 24-hour period.

What makes the toilet work so well?
MullToa toilets have a patented recirculation air process that provides the maximum amount of air throughout the composting material. The aerobic bacteria, which cause the decomposition, thrive in oxygen rich environments. Feeding more air to these bacteria is like feeding more air to a fire, it will compost hotter and faster.

Does a certain temperature need to be maintained in the room with the toilet?
Yes, during periods while the unit “is in use”, the room temperature needs to be 64F (18C) or higher. When the unit is not going to be used the temperature can go below this.

What about the fan? If the power goes out will it stink inside the building?
The airflow system is quite unique in that during a power outage, the air continues to flow (albeit more slowly) up the vent stack. It is based on the same principle as a wood fireplace or stovepipe chimney. A properly installed MullToa unit will not smell inside with or without a power outage (see installation guidelines).

Does the MullToa unit come with or need a Wind Turbine to help the airflow?
No. Wind turbines are not recommended. MullToa units do not need them and turbines will impede the airflow (aka… not a good idea!).

How about a heater?
The MullToa units have two heaters. The fan blows air over an upper heating coil and warms the air circulating inside the upper chamber. Warm air picks up more moisture than cold, thereby allowing for optimum liquid evaporation. The MullToa units all have a secondary plate heater located under the humus tray in the bottom chamber. The plate heater comes on when excess liquid is detected in the lower tray (MullToa 65 & 55 only), or the unit setting is turned to 10.

What about the MullToa 25, does it have two heaters?
Yes. The MullToa 25 has two heaters. However, the plate heater is only on when the toilet is set to 10. This unit is designed for lower use than both the MullToa 65 and 55. It is ideal for bunkies, boat house, pool cabana, barn, workshops, etc.

Can the MullToa units freeze?
Yes the toilet & contents can freeze without any adverse effects.

What about winter use?
For winter, you can use the toilet as soon as you arrive at the cottage, wait until the building/room has warmed up and the content of the upper chamber is thawed before turning on the toilet.

Where are the MullToa units manufactured?
They are made in Sweden. MullToa is the world’s largest manufacturer of waterless composting toilets. The requirements for composting toilets are exceptionally strict in Sweden and they lead most nations in pollution prevention.

What is the warranty?
A comprehensive 1-years parts replacement on all electrical components and body.

What is the cost to ship?
Most often shipping within Canada is included in the price of a unit. More remote areas may have a charge. Please call or email to inquire.

What do you mean by number of people using the unit and full/part time?
There is no industry standard for Users/People or Full/Part Time and this can be confusing. All manufacturers differ and this should be checked carefully and matched to your requirements.
MullToa specifies the number of Users/People, based on 5 uses of the unit per person, per day. (By the way, we allot the highest number of uses per person, per day).

Part time Use is up to five days in a row with a rest of a few days afterwards.
Full Time Use is more, at seven days a week.

MullToa User/People Model Specifications are as follows:

MullToa 65,
Full Time: Allows for Four People to use the unit (five uses per person a day).
Part Time: Allows for Six People, maximum five consecutive days, (five uses per person per day).
MullToa 55,
Full Time: Allows for Three People to use the unit (five uses per person a day).
Part Time: Allows for Four People, maximum five consecutive days, (five uses per person per day).
MullToa 25,
Part Time: Allows for Four People, maximum five consecutive days, (five uses per person per day).

Please let us know if you have any questions at all!

Click Here For Infomation on our different MullToa models.


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