5 Reasons You Need a Compost Toilet

Written by Madison Dapcevich

When building a log home, it’s easy to be swept away by the enamor of a self-sustaining, off-the-grid home with little carbon footprint. What many may overlook in bringing their dream home to reality is what to do with the doodoo. Compost toilets offer a solution to those who wish to maintain a small carbon footprint.

What is a Compost Toilet?

Just like a garden composter, compost toilets act as small-scale waste managers to create human-made manure, or “humanure”.  The perfect balance of moisture, oxygen, heat and organic matter create an environment where bacteria and other macro and micro-organisms thrive. In doing so, the natural process of decomposition breaks down human waste. Around 75 percent of this waste is made up of water that is evaporated during this process. The remaining amount of solid waste is converted to a soil-like material similar to humus, which can be used as fertilizer.

It may sound like a dirty job, but rest assured—the days of odiferous and uncomfortable outhouses are long gone. After your business is done, simply cover the waste with peat moss, sawdust or coconut coir to cover the smell while order is eliminated with a built-in anaerobic system. When the bucket is full, cap the waste and move it outside, rotating it every few weeks as you would a regular composter. When done properly, the end produce destroys bad pathogens that could have a negative effect on human health and the environment while transforming waste nutrients into fertile soil.

If you’re still not convinced on building your own system, we’ve broken down five reasons to consider including a compost toilet in your cabin design plans.

See also Environmentally Friendly Toilets

1. Compost toilets are truly off-the-grid and will lower your power consumption.

Ventilation and lighting aside, compost toilets use very little power. As much as 13 percent of energy used in the US is related to water. Compost toilets cut back on energy throughout the entire treatment process—from the septic system to the treatment plant—in turn helping waterways.

Take the Chesapeake Bay, for example. Here, nearly 1.5 billion gallons of wastewater from 500 sewage treatment plants flow into the bay every day. Human waste contains dangerous pathogens, viruses and bacteria which can harm wildlife and ecosystems.

2. They are sustainable and environmentally friendly.

A compost toilet is great in rural areas without access to septic or existing plumbing systems. Because they don’t need much in the way of infrastructure, these potties have a small impact on the environment. Treating waste onsite cuts back on environmental disturbances and financial costs of connecting to and maintaining vast sewage systems. Everything that goes into the toilet, including paper, is capable of being recycled, further reducing the need for commercial fertilizers.

3. Compost toilets are ideal in places that are prone to drought or where water is scarce.

More than a quarter of the average American’s household water use comes from flushing toilets. At five flushes a day, one person may use as much as 2,336 gallons each year. While federal law requires that toilets purchased after 1994 use 1.6 gallons or fewer per flush, outdated systems can use as much as seven gallons each time. Not only will you save money each month on your water bill, with a composting toilet you could also save as much as 6,752 gallons annually.

4. Humanure acts as a natural fertilizer to enhance growth of non-edible plants.

Waste created from a composting toilet can be used as an organic alternative to traditional fertilizer to help promote soil health. One person using a compost toilet can produce more than 80 pounds of organic humanure each year, and with nearly seven billion people on the planet it has the potential to serve as a renewable resource. Humanure is best used by burying the compost around tree roots, shrubs and garden beds of non-edible plants.

See also Composting vs. Incinerating Toilets

5. The entire system is self-contained.

There are two types of composting toilets:

• A self-contained system is connected in a single unit. These options are great when working with confined space or a multi-story house.
• A centralized system utilizes a large, centralized tank installed under or outside of the home where all waste is flushed into. This is a great option for an experience similar to the more traditional toilet.

Both systems eliminate the need to transport wastes for treatment and disposal (bye bye, septic system). Sewage and wastewater contain bacteria, funguses, parasites and viruses that can be dangerous to human health. By reducing the need to transport raw sewage (either via infrastructure or by cleaning septic systems) the risk of exposure becomes less of risk to people living in these areas.

As with anything, there are some disadvantages to using a composting toilet, including maintenance, more responsibility and commitment, and removing and maintaining composting systems can be gross and tedious. State laws vary when it comes to composting toilets, so be sure to know what zoning laws and requirements are in place before you do away with your doodoo.