DIY composting toilet in a motorhome

Trenntoiletten Selbstbau

Rolf's composting toilet in the Bimobil

Here Rolf presents his composting toilet project in his Bimobil.

He already has a lot of experience, because this is not his first composting toilet.
He built the first one with a blue Separett divider insert. The second one was built with a white divider from an alternative company (see pictures).

Trenntoiletten Selbstbau

Let's start with the installation dimensions:
  • The height from the shower floor to the lower edge of the bowl support is 470 mm in our case.
  • the support board is 15 mm
  • the height of the upper shelf is 510 mm
  • the depth to the back wall is 440 mm
  • from the back wall to the outer dimension of the urine bottle is 400 mm

The installation

This is installation in the smallest space with the best function.

It is clear that the urine container cannot be concealed because it would otherwise be too deep in the shower tray, i.e. it is slightly open and the container is therefore visible. If that bothers you, you should come up with something else, but not in such a small space!?!?

So, you will ask yourself, why is he converting his blue (note from me: Separett) to white?

Quite simply, I wanted to know what the difference was. At the same time I changed the system, not through the flap (old Thedf.) which is what I wanted at first, but to removal, etc. from the inside.

Discretion is the order of the day.


By the way, I have installed a permanent suction system, no matter what others say.

The question here is whether a larger or smaller urine container is a good idea. You get rid of the 5 litre faster, but the big one (10 l) lasts longer. And that's what I wanted.

It fits without any doubt and closes by itself.

It was a lot of work: the conversion, adjusting the mass, etc.

But it's a great solution now.

From the beginning, I wanted to get the system to fit the Thetford mass, and now I've done it.

By the way, the hole in the lid is drilled out with a 53 mm hollow drill bit, the sleeve mentioned fits exactly, if necessary a little off centre. Glue it with Sikaflex, add a little lubricant and you're done.

Basically, it's easiest if someone has the space to build a complete box in the depth and that's it, but as I said, I wanted to use the given space depth of 670 mm due to the Thetford cassette toilet.

If you want to know more about composting toilet inserts, read my blog article: