Komposttoilette im Tiny House: Wie sie funktioniert + meine Fehler
Building my tiny house is now more or less over and as with every other project there are a few things that don’t work out quite as well in the end. In my case it’s mostly my diy urine-diverting toilet or composting toilet and today I’ll talk about why that is and which solutions came to my mind. Urine-diverting toilets are definitely still a niche but since they are in so many tiny houses in the US and the movement is getting bigger more and more people learn about it. For all those who don’t have a clue about what it is and how it works: The idea is to divert urine and solids so that smells which come from combining these two do not come up in the first place. You don’t need a water-intense flush since solids and paper are collected and don’t need to be flushed. Apart from urine everything goes into a vented container and is later being composted or disposed of. Urine will either go into a container, which is great for travelers, or into the grey water, like in my case. You might ask, why an alternative toilet in the first place? The flushing toilet works just fine. A urine-diverting toilet does have advantages, number one being the small water consumption. Since I don’t have to flush, it’s great for those who work with a tank in their tiny house because you want to use as little as possible. But even without a tank it’s better from an ecological point of view not to use drinking water for flushing the toilet. Waste water: You only have grey water since there’s no feces in the water, meaning my plumbing is a lot smaller and the maintenance is easier. Plus you can drain it on the property if you have the permission because no feces etc. are involved. Generally speaking, if more people use the toilet, it helps reduce the workload of the sewage plant. However, I don’t totally buy into this argument because people will end up dealing with feces at home because they have to empty the toilet themselves and have to manage disposal etc. So a hygienic process at home has to be ensured lest we have more issues than a few centuries ago when we had quite different toilets. The biggest issue with the topic is where to put the solids. Composting is possible but you have to make sure the compost is separate from the ground lest the bacteria will get there while the composting is still on. The solids will have to stay for up to two years so it’s bacteria-free. Instead you can dispose of it regularly. Diapers go there too, so feces. This question is still not answered thoroughly so composting toilets are still somewhat of a niche. I think it’s an interesting concept and wanted to incorporate it into my home. I say diverting toilet rather than composting toilet because the latter is more common but the composting process happens outside of the toilet in most cases. Diverting toilet is more precise. Anyway, I’ll show you what the toilet currently looks like and what my issues are. Designed and built predominantly by my father, I hardly remember the building process since it was at a time when a lot in my home was happening at once and my head was all over the place so I didn’t pay attention to the toilet build as much as I should have. This becomes obvious now but we’ll find a solution to that. It’s a box, slightly angled so you can put your feet below it a little. That’s just more comfortable. To the left we have some storage and to the right is the toilet. The seat and the lid are by Separett, the Separett Privy, it allows you to build your own toilet. They also have full diverting toilets but also the inlay. I took that because it was cheaper and we loved diy. Liquid and solid get separated here and the back is shielded by a lid, you can pull here and the lid will open up. You can put in toilet paper and all solids. My father came up with a cool mechanism and it’s sad I can’t continue using it. Below you’ll find a bucket with a liner, compostable or not, depending on what you do with it. The rest goes in there, covered with a special soil in my case, I got this from Wohnwagon to try it out, and you can see the link in the description. I will continue using this soil in my new toilet. It’s neutral in smell and helps to compost stuff. My experience was very good so far and I got a big bag right away. That lasts for a while. The urine hose goes into the drain and back there is the vent to always bring fresh air in. When I moved in I used the toilet for liquids only to test every part separately to find out whether it actually works the way it should. It did for two weeks but then problems started to come up. Let’s start with ventilation. It’s pretty silent in the bathroom, as I showed you in the vid back then, but in the living room it’s quite different. The vent hits a frequency that produces a deep and very persisting noise. I didn’t notice that at first but started to get headaches and didn’t know why. Only when I switched off the vent it was gone immediately. So I couldn’t keep that running, but without a vent the toilet didn’t work as planned. Second, we added a siphon to prevent smells from coming up from the drain. That led to having to flush the toilet with a lot of water and we didn’t build it correctly because no matter how much water we added the smell still lingered. Normally when you flush the toilet it doesn’t smell anymore so we surely did something wrong. Third, the wood out of which we made the box, which were three-layer slabs, was not treated so it took on the smell pretty quickly, meaning after a while you always smelled urine a little. As soon as you opened the lid you could smell it on the outside. I could just paint it but there were more issues. For example, the heating pipes. They run inside the room, on the side of the toilet. We didn’t insulate them inside the box because the vent will bring in cold air so we wanted to prevent cold and damp corners so the heating pipes were warming up the toilet box. The idea was good but the pipes were so warm that you got 30 °C in that box which is perfect for smells. The toilet was too open in general. Instead of using the least possible space for the bucket and seal and vent it, we have this large box where smells can go in either direction and you have a lot of air volume to cover. Also, the pipes go through the wall to the kitchen and because they are not sealed the kitchen drawer will get this slight smell of … And then there’s a few small things which I’m totally responsible for so don’t blame it on my dad. I should have thought about that sooner. For example, the urine drain is fixed because of the siphon which means that we can open the lid of the toilet only so much. Which means that you can’t take out the bucket with the liner but only the liner without the bucket. And you want to trust the liner. But you’re glad if you don’t have to. Moving on to the lid, it works just fine and you can clean it easily but there is one spot where we cut it where it gets damp and soaks. So when I flush a little too hard and water gets back there in the other opening, it gets onto the lid and soaks. So it slowly starts to disintegrate. We didn’t think about that beforehand. Also, the wire for the cable pull goes over a sharp edge so it starts to fall apart and we would have to replace it anyway. Again, some issues might be small and easy to fix but the main issue is, when I enter the bathroom and get that smell as if I’d just been to the toilet, it’s just not how it’s supposed to be. I therefore decided to try the proper diverting toilet, the complete system by Separett, the Separett Villa. It’s the most common and it’s got the best reviews. Everyone who’s using it in their tiny house seems to be very happy. I think if one toilet can fix my issues, it’s going to be that one. I opted for the model with the weakest vent, only 2 W. That will hopefully be enough to let it run constantly without getting headaches. In my next video about the topic you’ll see the Separett and my first experiences. I’m very excited and hope to close that chapter. I have to remodel a few things in the bathroom because the box will go, the panels will have to be redone. But that’s how it goes sometimes. Not everything you plan in your head works out. A few notes on the alternatives because you might ask why I didn’t choose xy as an alternative. There are actually more toilets than the flushing toilet. Speaking of that one, I simply didn’t want to redo all plumbing to install the flushing toilet since there is no outlet there right now. All pipes would have to be bigger. More holes, remodeling the tech compartment as well, if I don’t have to I’d rather not do that. I also can’t be sure that every parking spot for my tiny house in the future will have the larger pipes since most tiny houses come with the smaller ones because they use diverting toilets. So the smaller pipes are more secure in that case. Now to the alternatives. There are incinerating toilets and freezing toilets. Seriously! They are interesting because they are completely waterless, you just plug it in and you’re good to go. But, number one, smells might still be an issue. But the main reason for me is that the power consumption is so high. Burning things or freezing things takes up a lot of energy and it doesn’t make sense for me to save water and money and then use a toilet that takes up more energy than my fridge. That would be the last resort. For what I’m doing here, permanent living, this is not an option. Chemical toilets as well, apart from ecological reasons, don’t make sense either. I’m excited for the Separett Villa and I’ll let you know all about it. Hope you’re not making my mistakes when building your own toilet. This just goes to show that not everything in my build worked out well. There are a few things that don’t work as they should. But there is always a solution. Diverting toilets are complex so you need to do your research. I learned that. I’m excited for the new one and I think I’ll see you next week on Saturday at 6 pm CET in my new video. See you and, as always, ciao.