Sun-Mar Excel Composting Toilet

self-contained, certified composting toilet
by Sun-Mar Corp.
The Excel by Sun-Mar is the best-selling composting toilet in North America and for good reason. It is a high capacity bio-drum toilet that is very simple to operate, features well proven technology and is extremely reliable. The Excel was the first ever self-contained composting toilet to be certified by the National Sanitation Foundation (NSF). So, when you purchase an Excel, you are literally purchasing a composting toilet that sets the standard.

The Excel has enough capacity that it can be used just about anywhere; in residences, cottages and even in light commercial applications.

To simulate residential use the Excel was tested by the National Sanitation Foundation (NSF) at maximum capacity for 6 continuous months, during which the Excel produced no odor and produced a clean, safe compost. Only Sun-Mar self-contained units are listed for residential and cottage use by NSF, whose Standard #41 is the toughest composting performance standard in the world.

The 2" vent is attached at the top back of the Excel and can be installed invisibly by running it through the wall and up the outside wall. For comfort the Excel has a sturdy detachable footrest which can be removed to pull out the finishing drawer.

In normal use the Excel can normally evaporate all liquids, however a " emergency drain is fitted at the rear and this should be connected if the unit is to be used residentially or heavily, or if prolonged power outages are expected.

Composting Capacity: 3-4 Residential 6-8 Weekend and Vacation Use.

Excel Specifications

Listed capacities refer to the amount of people, on average, using the unit per day. Do not pick a unit that is below your capacity.

Residential/Continuous (Adults/Families)

3 adults or families of 5

Seasonal/Vacation (Adults/Families)

6 adults or families of 8

Electricals must be connected while the unit is in AC use for proper operation

Maximum Amps (With Heater On)


Fan Watts (Required or Optional Hookup)

30 Required

Heater Watts (When Thermostat switches it on)


Average Power Use in Watts (Heater on 1/2 time)


Vent & Drains

Vent Pipe

2" PVC Thinwall

Drains (Required or Optional Hookup)

1/2" Drains, Optional Seasonal/Vac use, Required for Residential/Heavy Use

Weights (Lbs.) & Dimensions

Product Weight/Shipping Weight


Shipping Carton Dimensions (W by L by H)

28" by 36" by 36"

Depth Required to Remove Drawer


Vent outlet center distance from right side


Height to center of vent

28 3/8"

Unit Height/Width/Depth

32" by 22 1/2" by 33"

Rough-In Dimensions

Click on Thumbnail for exploded View

Click on thumbnail for exploded view

Country of Manufacture: CA