What Is an Eco-Friendly Toilet and How Does It Work?

At some point on your tiny life journey, you are going to need to think about toilets.

Not the nicest of topics, but there is no getting around the fact that everyone needs to use one.

There are quite a few different ways to tackle the problem in a tiny home. But if you want to be kind to the environment as well (and why wouldn’t you?), your choices are more limited.

One of the main benefits of an eco-friendly toilet is that it will be ‘dry flush‘, that is, no water is used to flush the waste away.

That means you will have to collect the waste in some other way for disposal later.

Here is a table of contents to allow you to skip down to the information you want to read about…

One option would be to use a toilet that collects the waste in a bucket which you then dump in a hole in the ground. Not that eco-friendly (or user-friendly!) and may be illegal in some communities anyway.

It’s always best to check with the local authorities what you are allowed to do so that you stay within the law.

The other method is to use a composting toilet, a much safer, cleaner, and environmentally friendly alternative.

What is a composting toilet?

A composting toilet is where the human waste is mixed or covered with an organic composting starter material.

The name is a bit of a misnomer as in fact, in some so called composting toilets, the material is not in the toilet long enough to even start composting.

They all, however, allow you to collect the material for further decomposition in your compost pile or for disposal.

Using one is not as bad as it sounds and strangely enough, when done properly, there is little or no smell.

Well in or around the toilet anyway. Disposal might not be an odor free experience as we shall see later!

How do composting toilets work?

There are two main types of composting toilet.

The first is where both liquid and solid waste goes into the same receptacle.

The second is where the two types of waste are separated into different receptacles.

The first type is not really a composting toilet as the bucket is usually emptied after a week or so. The composting is done in your external compost pile where you empty the contents.

This type of toilet could also be a portable composting one if desired as they can be as simple as a bucket with a seat on top.

Usually, though, for use in a tiny house, they would be made of a more solid wooden structure with a removable bucket.

The second type has separate bins, one for solids and another for urine. An example of this is the Nature’s Head composting toilet which works very well in a tiny home.

The Nature’s Head and other similar toilets work by keeping the urine away from the solid matter so that sewage sludge is not created. This is one of the main causes of that horrible smell associated with non-flushing toilets.

The solids, including the toilet paper, are mixed with an organic composting material. This is so that it starts to naturally decompose and break down.

A vent and small low power fan (think the type used in a computer) keep the air moving, removes smells and helps to speed up the aerobic process.

When completely composted, human waste becomes a nutrient-rich fertilizer that is free from pathogens and viruses. These are all destroyed in the decomposition stage by friendly bacteria.

How to use a composting toilet?

The composting toilet with a single container will have a large removable bin built into it. You can line this with a biodegradable liner or just leave as it is.

The toilet will usually have a seat and a lid so you can sit or stand at it as normal.

The difference will be that after you have finished, you cover the waste with a suitable compostable material. This stops any smells and leaves it ready for the next user.

When you look into the toilet you will be looking at the covering so it’s important this is done right!

Believe it or not, if done properly this actually works. You will get very little if any smell from the toilet and it is not unpleasant to use at all.

There are several materials that could be used as your covering, just make sure it’s carbon based. An easy test for this would be that if left to dry out, it could be ignited with a match.

Some example materials include:

  • Sawdust – readily available but must be hydrated before use if dried out. Just leave it outside in a pile if you can for a little while so that it gets damp and becomes biologically active.
  • Peat Moss – must be Sphagnum Peat Moss. One of the most effective materials to use and so easily available. However, some may argue that as it’s not an environmentally sustainable product we should not be using it at all.
  • Coconut coir – this is a natural fiber found between the outer coat and the internal shell of a coconut. The waste from the coir industry is compressed and formed into bales which are readily available and cheap to buy. The coir needs to be rehydrated before use by breaking off what you need and soaking in water
  • Shredded junk mail – shredded paper is another alternative. Again it would probably be best if moistened first.
  • Wood shavings – These need to be small and thin, otherwise they will be too big to decompose easily. They also do not provide the best odor prevention.

For both types of toilets, you will need to empty the bin based on usage.

If you used a liner, then it’s as easy as gathering this up, sealing it and then disposing of it – see below for ideas.

If no liner was used, then the bin needs to be taken outside and the contents disposed of.

The second type of toilet is the one with the two different compartments.

Again, this will have a seat and a lid so is easy to use. The main difference is that men will need to sit down even when not using the ‘full facilities’.

Looking down into a toilet like the Nature’s Head model, you will see a large hole that is covered by a flap and some smaller holes towards the front that is open.

These smaller holes are through which the urine will flow down into the urine bottle.

The flap over the larger hole will need to be lowered when needed so that the solids drop straight into the bin below.

In the solids bin, you will already have a layer of organic starter material, which is usually Peat Moss or Coco Coir, that you placed in the bin to start with.

After finishing you close the flap and turn a handle on the side of the toilet to mix the new material with whatever was already in there. This keeps the composting process going and starts breaking down the waste.

The urine receptacle will need emptying quite often and it’s important to not let it overflow for obvious reasons. Getting at the bottle is easy on most models and then it’s just simply a matter of removing it and disposing of the contents.

The solids bin will often last up to a month or more depending on usage before needing emptying. In fact, the longer it can be left the better as the composting process can really get going.

There is no need to line the solids bin in this type of toilet as anything that’s left in there after emptying just becomes part of the next lot of compost.

The bin will be easy to remove on most models and can be taken outside for disposal (see below for where to dispose of the contents).

Why use the composting toilet?

You may be thinking at this point that it seems like a lot of hassle using a composting toilet.

Well, apart from the obvious benefit of not having to deal with emptying raw sewage at the RV trailer park, there are many reasons to think again:

  • Composting toilets are compact and self-contained.
  • No need for plumbing as they are dry flush toilets.
  • No flushing means they are silent in operation (very important in a tiny house!)
  • If you live on private land you can build your own compost bin to dispose of the waste.
  • If composted properly, the toilet contents turn into a great fertilizer to use around your garden. What could be eco-friendlier than that?

Where to empty a composting toilet?

We’ve already covered how to empty a composting toilet above, but where can you dispose of the contents?

This is actually quite straightforward.

If you have a single receptacle type toilet, then the preferred method is to empty this into your own compost heap for further decomposition.

Sometimes this is not practical so you will need to empty into a biodegradable bag and put in the trash. If that’s what you will be doing it might be best to set up your toilet so that the liner is already in place.

That will make it a much easier and cleaner operation.

If you don’t use a liner, then the bin will need thorough cleaning before putting back into use.

If you have a composting toilet with urine diversion, then you have two types of waste to dispose of.

Urine can be safely poured down the standard toilet at a rest area or wherever you are parked up. You could also dilute this and use it around trees and shrubs as a fertilizer as it’s rich in nitrogen.

If you have your own compost pile, the urine can be poured into that neat as it adds lots of nutrients to the mix.

Be warned, though, dumping the liquid waste is quite an unpleasant task as it does smell pretty bad when emptying.

We have heard of some methods to stop the urine smell from getting really bad when dumping it. These have limited success but might be worth a try (not at the same time, though!).

First of all, try adding 3 tablespoons of raw sugar to the urine tank before replacing in the toilet and if that doesn’t work put a cup of vinegar in the tank instead.

You might expect the solids bin to be even worse, but in actual fact the opposite is true.

Because of the way toilets like the Nature’s Head works, the mixture in the solids bin will already be decomposing by the time you come to empty it. This means you will notice a damp earth type smell, but nothing more.

Note it’s a good idea to leave at least half a day between the last use and emptying to allow the latest material to settle in a bit.

The material from the bin is best put into your own compost heap of course. Like the single type of composting toilet, you can also empty the waste into a bag and dispose of in the trash.

Unless you’ve not been using the toilet for a long time then the compost will not be ready to put straight on your flower beds, unfortunately.

This usually takes 6-12 months of nature’s work before it’s ready for that. That’s why it’s such a good idea to have your own outdoor compost arrangement set up if you can.

Once emptied, the bin can be put back in place and a new layer of organic material added ready for use. No cleaning required unless you want to wipe around the outside with a cleaning wipe.

How to maintain a composting toilet?

Aside from the regular emptying cycle, these toilets are fairly easy to maintain.

Spraying with a water and vinegar solution and then wiping around with a paper towel, for instance, is all they will normally need.

If you are an ‘I like to disinfect everything’ type of person, then you can do that too.

Be careful when cleaning the type with two receptacles to make sure no liquid gets into the solids bin, though. You don’t want that turning into a gloopy mess!

Also, many cleaning and antibacterial products will kill the good bacteria doing the composting work.

Some users reported that models with a separate urine tank sometimes get a buildup of scale inside it after a while.

One way to get rid of this is to put about 3 inches of vinegar into the tank, add some small stones or pebbles and replace the cap.

Then give it a vigorous shake to break up the scale and empty it out.

On toilets like the Nature’s Head, there is a fan for ventilation and some air duct coverings that stop bugs getting in which will need checking.

These are important to keep in good condition so check them every month or so.

How to install a composting toilet?

Installing both types of compost toilet is a lot easier than installing a wet flush type.

The single tank type can be installed almost anywhere there is room to put it. The only consideration would be that it’s somewhere with easy access to carry the tank outside for disposal.

These toilets need no electricity, water supply or anything else to work. Just the toilet itself and a bin for the covering material, that’s it.

The dual tank models require a little more thought but are still simple to put in.

The main considerations will be where to vent the air hose and how to get 12V power to the fan.

The air outlet hose can be vented through the floor, wall or ceiling, whichever is most convenient.

The fan needs to be running all the time so will either need connecting to an always-on power source or fed from a solar powered battery for instance.

Both will usually be something the average tiny home owner can rig up.

Apart from that, as the units are self-contained you just need to find somewhere to put it. Just make sure that you leave enough room around it to turn the handle and remove the tanks for disposal.

What is the best composting toilet?

For the best, all round convenience and ease of use, then the composting toilet we have mentioned a few times, the Nature’s Head, ticks all the boxes.

Whether for use in an RV type or static tiny house, this model has become very popular amongst eco-conscious tiny home dwellers.

In fact, even people who would normally just go for a wet flush toilet have become converts when finding out how simple and clean these are to use.

The unit is made in the USA and comes with everything you need except for the external vent as that depends on where it will be sited.

The built-in fan and vent hose can be mounted on either side and the toilet seat is molded as part of the top section for easy cleaning.

The seat is full size as well rather than the mini size found on some other models.

You could also make the model completely electrical power free by running the vent hose to a solar powered vent.

An Alternative

Although not a dry flush toilet review, we should mention an alternative that saves on water and has an easy waste disposal. The downside is that it’s expensive to run and is not as eco-friendly as the Nature’s Head.

This is the Laveo Dry Flush Portable Electric Toilet. Using a completely different design, this model effectively shrink wraps the waste in a foil material with each ‘flush’.

The foil comes in a canister that fits in the toilet and sits inside a plastic liner. When the canister runs out after around 16 or 17 flushes then you just gather these up in the bin bag and dump in the trash.

Very clean and easy to use, this is growing in popularity especially amongst weekend and occasional tiny house dwellers.

The unit comes with a built-in rechargeable battery so will need to be charged up from a standard socket occasionally. This drives the flushing mechanism which is a motor and vacuum device to wrap the waste up nice and secure.

No composting is involved, and it does not use any water or chemicals.

How much does a composting toilet cost?

The Nature’s Head composting toilet is available for just under $1000 which is less than some of its competitors. If you look around at other similar models you will find they can cost twice as much in some cases.

You can, of course, do this very cheaply with your own do-it-yourself single bucket type composting toilet. You may find that it’s just too basic for your needs, though, even more so if it is going to be your main facility full time.

The Laveo Dry Flush Portable

Electric Toilet comes in at around $600 with a 3 pack of refill cartridges costing around $55.

That works out to around $1 per flush so may be too expensive to use full time. The manufacturers are working on making this more economical and eco-friendly to use, though.

Where to buy a composting toilet?

We have found the best price for the Nature’s Head is through Amazon. You can buy the toilet, a block of coir for composting and a spare urine bottle for just over $1000 at the time of writing.

I have also found another source with a similar price point to Amazon that you can see here.

The Laveo Dry Flush toilet is available at Home Depot and you can also purchase it online at Shop Tiny Houses. You can also get the refill cartridges and a floor mounting kit for it.

That wraps up our quick introduction to eco-friendly or composting toilets that you can use in your tiny home.

Hopefully, you will have more of an idea now on how one of these amazing devices can fit into your lifestyle, even if you are not considering going tiny!

Don’t forget to check out the models we recommend when you are ready to fit a dry flush toilet.