Let’s talk about composting toilets

Welcome to Le Shack and my blog about life in an off-grid cabin in France.

The subject this week is not for the squeamish for we are going to talk about composting toilets. That’s not a phrase you hear very often for the simple reason that we don’t talk about toilets, or certainly not what we do when we are in one. It’s one of the last taboo subjects, a topic of conversation guaranteed to ruin any good dinner party. I say this from experience as, whilst there are many aspects of our off-grid life that people are interested in, how we deal with our toilet habit is not one of them. If I bring the subject up the reaction is a horrified fascination that lasts for about twenty seconds and then it’s time to move swiftly on.

People make certain assumptions about composting toilets, myself included until I had one of my own. First and foremost is that you only have one if you have no choice; it is a means of last resort and an unpleasant experience to be endured under duress. Secondly, the whole process must surely be a smelly, dirty, and un-hygenic affair. People recall images of the old-fashioned privy that they’ve seen in dated films, stinking hovels that have the nose wrinkling in disgust from twenty paces. And as for physically removing the unmentionable contents of our bottoms from a bucket into a composting bin at the bottom of the garden, well….. there are no words to describe the awfulness of it all.

But it doesn’t have to be like that.

We have a composting toilet through choice. There is a septic tank out in the garden and, if we wanted to, we could use up valuable space inside Le Shack plumbing in a conventional loo with flushing water. The lady who lived here before us chose not to do that and neither do we. There are three sound reasons for this.

Before I begin let me reassure you that I am not going to go into intimate detail about what we do in the toilet, although it is tempting because the subject is fascinating. But I will use the words ‘poo’ and ‘pee’ and trust that this is acceptable to even the most squeamish of readers. Another couple of words that needs to be introduced are ‘humanure’ and ‘bio-solids’ both of which describe human waste or human manure.

The three reasons it makes sense to have a composting toilet are because it saves water, it saves energy and it recycles a valuable commodity. Let’s look at the water issue first. Flushing the loo accounts for about 30% of average personal water consumption. On a planet where the water supply is finite, we should be doing what we can to conserve it, not throw it down the toilet – literally. We are the only animal that deliberately mixes water with our waste, thus making it far more bulky and expensive to get rid of. This leads us on to the second point which is about energy consumption. There is an inherent, invisible – and therefore easily ignored – cost both to conventional toilets themselves and how we remove the waste that they generate. The manufacture of a toilet requires energy; in fairness our plastic buckets also require energy but they are simple affairs compared to the intricacies of modern toilets. Treatment of our human waste at sewage plants also requires energy, as does the transport of waste from septic tanks. We are all under pressure to reduce our carbon footprint, and a composting toilet is one way to do this.

Lastly there is the aspect of recycling and the clue is in the name here. ‘Humanure’ produces compost, just like your vegetable compost bin, rich in nutrients, helping to bulk the soil up so that it retains moisture and playing host to a mass of microbial and invertebrate life. There is an art to making good compost, vegetable-based or human. It remains to be seen how well ours will turn out.

There is a fourth reason to have a composting loo but this only applies if your loo is outside, as ours is, rather than in a normal house. Our loo shed is admittedly a bit of a rough affair at the moment. I do intend to pretty it up, but there are other priorities in these early days. It is a wooden shed with a plastic laminate roof and as the wooden slats in the walls have dried out and separated by a few millimetres it is well ventilated. No bad thing I can hear you thinking, but that open structure has another benefit. When I visit our loo-shed in the morning I can hear the birds singing in the hedge behind me. When I go out at night I am treated to the sound of the owls hooting in the giant oak less than ten paces away. I am doing a natural thing in a natural place. I wouldn’t have it any other way.

Brace yourselves – it is time to move on to the nitty-gritty of composting.

There are many different ways to build a composting loo but I will just stick to what we have done, which is the simplest option. You need a wooden box, in which you cut a hole and fix a conventional loo seat. Inside the box you place your bucket. The front of our box is removable, so when we want to replace a full bucket with an empty one, we simply open up the front of the box, slide one in and one out, firmly pushing a lid on top of it, and the job is done. A bucket next to the loo holds a store of shavings and a scoop. The empty loo bucket is primed for use with a layer of shavings on the base and every time we use the loo we sprinkle a scoop of shavings over the top. This is key for this is what stops it smelling and, for the record, it really doesn’t smell – at all.

Some people like to keep their buckets dry, by which I mean poo only, others say it is fine to combine pee and poo. We are experimenting with the latter for our first year. We have four buckets and once all four bucket are full, which takes a month or so, then it is time for a visit to the composting bin down in the field. Michael has re-cycled three old pallets we found in the hedge to provide the walls of our composting bin. He informed me very early on that he would build the composting bin, but that it should be my job to empty the buckets in to it. A woman’s work is never done…….

The base of the bin is lined with bracken. We used this as it was to hand, growing in wild abundance in our field, but you can also use straw. The important thing is that the stack needs to breath, to be aerobic, in order for it to work properly. The contents of the four plastic bins are duly poured, very carefully, in to the compost bin, then generously covered with more bracken or straw and left. When I come down with the next four bins I will pull back the bracken with a fork used only for this job, make a hole and pour the new buckets in to that hole so that they can benefit from the heat already there. Apparently the stack needs to be kept flat, not heaped, and definitely not turned or disturbed as that reduces the heat and slows everything down. There were no unpleasant odours either during this process of filling the compost bin or afterwards, when we might walk past it.

There are four elements to successful composting and these apply to vegetables as well as humanure; temperature, moisture, oxygenation and time. We fully expect to have to leave this bin, once it is full, for a year or maybe two. Once the humanure has turned fully into a friable compost it can be used as a fertiliser for the garden. If it reached a good hot temperature, it is perfectly safe to use it on vegetable beds but this is a matter of personal choice. As we are only here for the winter we won’t have any vegetable beds, but we are looking forward to using it around our trees and the few shrubs that we have.

And there you have it – wasn’t so bad, was it? Our efforts with our composting toilet may seem a small, insignificant action in the larger scheme of things, but it makes us feel better to know that at least we are trying to do something towards a more sustainable lifestyle. If all of us undertook one small change like this it might add up to something wonderful.

I have something special for you next week – a FAF blog, which is our personal abbreviation for flora and fauna. We have been truly amazed at the proliferation of wildlife of all shapes and sizes that keeps throwing itself in front our camera as we walk, or sit, or potter about on the land so there will be lots of pictures to share with you – all of which are much nicer to look at than a composting loo!

For this week I leave you with another video and a glimmer of hope as the coronovirus figures in France are beginning to go down. I hadn’t realised the full extent of how they been depressing me until I felt so hugely cheered up by the fact that the trend is very definitely going down, although not without the odd blip in the wrong direction.

Wherever you live I hope things are moving in the right direction for you as well. We could all do with a bit of good news.

Take care and see you next week.

MJ