How do composting toilets work and are they suitable for shepherd huts?


If you want to set up a glampsite but can’t connect to mains drains or a septic tank, or if you’re looking for an environmentally friendly alternative to the traditional loo then the composting toilet may be the perfect solution.

What about the smell?

Many people are nervous about installing composting toilets as they believe that they will be smelly and unhygienic however when fitted correctly this isn’t the case.

How do they work?

The internal workings of the compost toilet are not particularly complex with the key to odour-free composting being separation. Human faeces in the presence of oxygen naturally breaks down into pathogen-free compost. Urine, which is sterile on exit and full of nitrogen makes for a superb fertiliser. The trick is in separating the liquids from the solids.

Whilst models differ in their sophistication they generally overcome this with a wee separator or twin bowl system which funnels solid and liquid waste capturing them in separate containers or diverting liquid waste into soak away.

For the process to work, moisture levels in the solid waste need to be controlled: too dry, and the mass decomposes slowly or not at all; too wet and anaerobic organisms thrive, creating nasty whiffs.

The solids are stored until fully composted, a process that generally takes between six to twelve months depending on the conditions when it can be added to your regular compost and used on the garden.

Which composting toilet?

There are various off-the-shelf models available such as the Separett or Natures Head units which can be used entirely off grid with the aid of solar power to run an internal fan.

Separett Composting toilet

Alternatively, we can build a composting toilet using a basic urine separator which gets the job done with the minimum of fuss. These toilets can be housed in purpose built buildings, designed to your liking and perfect for off grid Glampsites or they can be situated in a bathroom inside a shepherd hut.

Basic composting toilet
Basic composting toilet box

Urine separation & disposal

The urine separator we use is designed to fit standard piping and has attachments made from recycled plastic.
Liquid waste can either be collected in a container and used as used as a fertiliser for non-food plants (mixed about 1:10 with water) or diverted to a gravel filled, grass topped soak-away via a pipe, where it will feed nearby plants.


To prevent human waste producing excess nitrogen in the form of ammonia (the smelly bit) you need to provide the bacteria in your loo with a balanced diet of nitrogen and carbon. Our waste contributes the nitrogen and a soak, such as sawdust, straw, shredded paper or cocoa shells adds the carbon. Getting this balance right is essential for a whiff free toilet; fortunately, it is also fairly simple.

Which soak you use and how often will depend on the type of composting toilet you choose. If you opt for a self-contained system with an internal fan, such as the Separett then a layer of cocoa shells (easily purchased from garden centres or online) scattered across the bottom of the empty container should be enough to introduce air pockets and begin the decomposition process. However, a more basic composting toilet will benefit from a handful of your chosen material after each use.


How often you need to empty your composting toilet depends on how often it is being used and how big your containers are. Composting toilets can be built to house a large wheelie bin sized container which will clearly take longer to fill than a smaller bucket sized receptacle.

When the toilet needs emptying simply remove the container and set aside until the contents have broken down into compost. At this point simply add it to your existing compost heap for use on your garden.

If you think an off-grid glampsite might be for you and you want to find out more about how we can can design and build you the perfect shepherd hut to go with it, then get in touch and we’d be delighted to help.
Tel:  07761 983312

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