Do composting toilets smell? The Best Answer

Are you thinking about installing a composting toilet at home? You care about the environment and want to live in an eco-friendly home. In the USA, household toilets use up as much as 30% of water daily.

You do not want a traditional toilet in your home. But you are also curious to know ‘Do composting toilets smell?’ Nobody would like to live in a stinking house! This is a question that arises in most people’s minds when they hear of composting toilets. Lay your fear to rest. It is possible to have a fresh and clean bathroom that has a sustainable toilet.


If you learn about the method of processing waste and odor control in a composting toilet, it would make you more confident. So read on.

Composting Toilet – What is it?

The sewage treatment system of a composting toilet doesn’t use water to treat human excreta. It is a dry toilet that uses an aerobic processing system. Human waste is turned into compost, which is safe and usable.

Responsible homeowners are increasingly turning towards composting toilets. Compared to flush toilets, these need very little to no water. If you want to break down the waste quickly, you will have to spin or turn it.

A composting toilet can turn human excreta into fertilizing soil. But you have to ensure there is a balance between certain elements like oxygen, heat, moisture, and organic material. With the right balance, you will get a successful decomposition and a smell-free bathroom.

You will need special toilet paper so that it composts well. Adding sawdust or leaves to the toilet can help to reduce the smell.

You have simple systems that consist of a bucket to more advanced systems that use ventilation systems.

Does a composting toilet have less smell or a better smell than a regular toilet?

Surprisingly, the answer is ‘yes’ but it depends on how it has been installed. If you want practical advice, we would suggest you get a composting toilet with a big tank and fan. You will also have to add sawdust to remove the smell. The exhaust fan of the tank constantly lets out exhausted air through the vent. A composting toilet works with negative pressure. Whenever someone opens the toilet lid, the bathroom air gets pulled down into the basement tank via the toilet and let out outside. But a negative pressure also ensures that oxygen is not sucked out of the bathroom.

However, there might be a little stench of urine, especially if your composite toilet has separate compartments for solid and liquid waste. Having a urine diverter or heater that evaporates the urine helps. Urine does not get composted like a solid waste. If you install a composting toilet properly and maintain it, then there will be no foul odor at all. Composting toilets are designed in a way that bad smell is diverted.

But you should not get too concerned about that because the natural composting process gets rid of all bad smells by sending them out through the outdoor vent. You should.t have to worry about the toilet bowl smelling with the presence of the exhaust fan, vents, and negative air pressure at work.

The Pros and Cons of a Composting Toilet

If you are still undecided, having a list of positive and negative aspects in front of your eyes might help. Before buying a composting toilet, you should have all the honest information – both about its potential benefits and issues, if any. You will be able to measure the pros and cons from all angles after going through the lists below:


  1. Less water consumption. An average family can save 30,000 liters of water annually.
  2. A solar panel can be easily connected to a composite toilet for the functioning of the exhaust fan.
  3. After installation of a composting toilet, there will be negligible recurring costs. You have to only buy an enzyme bottle occasionally.
  4. A composting toilet has no negative influence on the environment. It is a boon as it cuts down on the use of chemicals in treating raw sewage. A composting toilet doesn’t rely on a sewage plant.
  5. The total installation cost of a composting toilet might be lower if you don’t need a septic system because of this.


  1. You will be manually required to handle composted waste as no water flushing is there.
  2. Small energy consumption is needed to run the exhaust fan. A traditional toilet uses no power for flushing.
  3. The initial cost is more than a traditional toilet.
  4. The space might be an issue if you desire to buy a more luxurious and bigger split system composting toilet.
  5. If you fail at maintaining the above, your toilet will stink up your home. It can also be dangerous as the waste can ferment and attract flies.
  6. Some people visiting your home will feel uneasy about going to a composite toilet.


If you have read this far, you already know the answer to the question ‘Do composting toilets smell’? It is a reassuring ‘No’. You can safely consider installing a dry toilet in your home. It will not cause any stench. At worst, you might get a little mulch-like smell or a woody smell. For proper maintenance of a composting toilet, avoid using harsh cleaning agents. The chemicals present can kill healthy microbes because microbes work hard to keep the toilet smell-free. For optimal functioning of the toilet, keep the lid closed when not in use. This will keep an adequate amount of heat inside the toilet and also keep it free from bugs and insects. Be attentive towards the moisture content. Don’t let your composting toilet be wet. Otherwise, it will be a hindrance for decomposition and will result in the emission of odor.

Now go ahead, save water, give back to nature and install that composting toilet you have been thinking about!