While Architectural Digest describes yurts as “an architectural wonder of the world” — and it is without doubt — inside my yurt it’s the loo that’s the showpiece.
Sanicompact43 – the ultimate toilet
It’s Saniflo‘s Sanicompact 43— a very superior toilet in every way. It’s high quality ceramic; it’s almost silent; it’s about the most waterwise-efficient toilet you can get… and it took less than 5 minutes to install in the yurt! And it has a soft-close lid & seat — you just tap it and it slowly closes on its own. Continue reading →
All the blackwater from the yurt’s toilet goes into the biodigestor. And so does all the organic waste from the kitchen. Methane gas output is increased by fats, oils, greases and sugars, and you can use the gas for cooking and heating. Another byproduct is liquid fertilizer, which you can use in the garden. You won’t need to buy fertilizer again!
The biodigestor: The bottom tap drains liquid fertilzer, the tap on top is the gas outlet and the blackwater input pipe is lying across the top of the tank, ready to be inserted into the tank.
The tank cost about R200 from Peninsula Drums and all the other fittings are from Overberg Agri and cost about R100. So… blackwater sorted for about R300! And all byproducts can be re-used. What on earth are we doing pumping all our effluent into expensive reticulation to expensive sewerage treatment works kilometres away? And unlike septic tanks, there is no danger of polluting groundwater.
In 1980, India had over 9 million biodigestors in operation. Today the number can’t be counted because they are even found on apartment balconies, primarily for organic waste to provide cooking gas for the inhabitants.
My solution took less than an hour to make. I cut holes for the liquid fertilizer and gas output pipes, and inserted tank connectors with taps. How to get the tank connector into the drum? Take a very thin piece of wire and insert it into the drum and guide it to come out of the hole where the tank connector has to go. Feed the tank connector onto the wire and pull it into the hole, where it needs to be tightened.
For the blackwater input pipe, I cut a hole into the one screw top, inserted the fittings into it and connected a piece of PVC pipe.
The other screw top remains to be used for organic waste and checking levels inside. Once the biodigestor starts producing gas, a similar but shorter pipe will be inserted to stop gas escaping when organic matter is added.
The drum should be painted black to prevent algae-producing UV rays penetrating the drum. (If that happens, your methane will be replaced by carbon dioxide.) I’m going to wrap the drum in thick black plastic which I already have. Bear in mind, the biodigestor needs warmth, so it’s located on the sunny side of the yurt.
Here are two videos which will tell you everything you need to know about biogas units:
How to build a biogas unit
You can also buy recycled flowbins from Peninsula Drums – really quite a remarkable award-winning company.
How to build a biodigestor
The biodigestor is only possible because of the Saniflo Compact toilet. Firstly, it macerates and pumps the effluent to the drum. The drum can be above the ground. Secondly, the Saniflo unit only uses 3 or 1.8 litres of water per flush, compared to the normal 6–10 litres of conventional loos. The biodigestor tank can be much smaller and is far more efficient with lower water volumes.
Now, all the unit needs is some blackwater and a bucketload of cow manure to kickstart the anaerobic process. It takes about a month for gas to be produced, or less since the blackwater is macerated.
I had just gone to sleep one night… I knew it was going to be windy but the winds were well within what the yurt had been through before. And then I became aware of the sound of the wind just rising and rising. I waited for the gust to end but this was no gust. It was like a runaway train, just gathering momentum. I jumped up and went to the door which was already bucking under the strain. I leant hard against it, wondering if I could hold it back for the next two hours when the wind was due to drop. I didn’t have to wait. The door broke loose, knocking me out the way, and came to rest in the centre of the yurt, flattening the services wall in the process.
I scrambled up to fetch my dog and rushed him into the vehicle for safety, and caught my breath. My mouth was bleeding badly -from lacerated cheeks and lips. (Later I discovered my body was covered in the worst bruises I’d ever seen.) Looking back at the yurt, it was gone…
DEVASTATION: The yurt was blown right off the platform. The walls were flattened. A quarter of the floor had been ripped up. The yurt’s contents were spread across the field.
This was a traumatic night. On my first night back in the yurt after it was rebuilt — during the next storm — I understood the real meaning of Post Traumatic Stress Disorder (PTSD). Every time I closed my eyes to sleep, I saw the roof disappear, or the door come flying towards me, or a gap appear between the wall and the floor, or, or, or…. I had to open my eyes to prove it wasn’t true. Fortunately that didn’t persist.
Peter Kastner let me stay in the “Trailer” — a whimsical place to stay — while I regrouped and gathered my thoughts. I kept asking myself, “Am I arrogantly trying to achieve the impossible?” Can I really beat the wind and Mother Nature?
So I made a plan and — before I outline that plan — I’ll give you the answer. I can’t beat it but I can cater for it. The yurt has withstood two more storms now, one reaching wind speeds of 121km/h. During the one shown below, the inside of the yurt was a sea of calm while noise raged outside. The walls hardly rippled, and — most times — there was just an occasional lazy flapping on the roof.
Forecast on the Windy app: the winds on the mountainside are almost permanently the magenta-coloured gust speeds shown above… or more! The wind comes barrelling down the mountain kloof that opens into this “idyllic” copse of trees. In the time I’ve been here, two trees have blown over.
Firstly, a note of warning about the Windy app. It’s not wholly accurate but it is good for warnings. It shows the same weather in the village as on the mountainside where the yurt is located. But while Stanford can be quite pleasant, the yurt can be buffeted in a gale. Even 200 metres down the mountainside, a howling gale turns into a light breeze.
What was the plan?
A (more) level floor
Given the total devastation, I had the opportunity to rectify one problem — levelling the floor. The slope on the first floor just encouraged the yurt’s structure to slide off the base. Just after I erected the yurt and before I attached it to the floor, I woke up to find it had just slid off its base in a medium wind. That’s when I realised how light the yurt actually is. The total weight of the walls, covering, rafters and roof ring is only about 150Kg. So the weights on each of the 16 points where it meets the floor is less than 10kg at each point.
Make it as air tight as physically possible
This was a big issue and I had to address several components:
The Roof Dome
I had wanted to get a plastic dome like Yurta has, but there are long lead times getting one made.
The roof dome on Yurta’s yurts
The camera decided to do it’s own thing… creatively. It still gives an idea of what the roof light looks like.
I had been using a translucent sheet of tunnel plastic tied to stays in the ground. This worked well because it was easy to open and close, although it was challenged in strong winds.
I needed a fast solution that would be totally air tight. So I bought a sheet of 1220mm square 9mm plywood, cut a circle and the opening to match the roof ring, and glued a sheet of tunnel plastic onto it. The seal is a strip of self-adhesive foam rubber (used for door jambs). Four bolts hold this tight to the roof ring. It works brilliantly! And if you are going to be using the yurt for camping trips away, it’s far easier to transport.
It can be opened and closed — with some effort because you need to use a ladder to get to the roof — and the ideal solution is for it to be attached by a screw jack which can be opened by a long pole. I couldn’t find any locally.
A screw jack
The issue of the door’s position
Everybody I spoke to said the door needs to be at the opposite end to where the bad weather comes from. I said that the door and its frame, if they are the strongest elements in the yurt’s wall, need to anchor the yurt against the bad weather.
So the door is more sturdily connected to the wall than it was before, and it’s also anchored, at the top and bottom on either side, by wire stays connected to one-metre steel posts hammered into the ground.
In addition, and to make using the door during a gale still possible, there’s a 3m wide x 2m high wind deflector. It’s basically two sheets of shade cloth between wooden posts. (I’ve read of people doing this with broomsticks and stays, but I wasn’t taking chances.) This has worked well.
Sealing the wind gap between the walls and the roof.
I’d used some bubblewrap as insulation against the morning sun, which was wrapped over the tension cable to form two layers hanging down and wrapping under the floor. This formed a fairly tight seal against the roof and seemed to be the solution.
So I applied this to the entire wall and in light winds it seemed to do the trick.
Bubblewrap hung over the yurt’s steel tension cable to create a better seal.
Then, while I was writing the previous story and waiting for the first real storm to hit, I looked at the pictures of traditional Mongolian yurts I used there and thought… wait a minute… I’m missing something — the rope bands around the yurt. So using existing rope and the eye-hooks in the door frame for the wire stays, I wrapped two lengths of rope around the yurt diagonally.
As the winds rose… there was no flapping and almost no wind entering the yurt. So I rushed off to buy more eye hooks and more rope, and now have three lengths of rope wrapped around the yurt for really bad weather. The windows can’t be opened when the ropes are in place, but I really don’t want the windows open when there’s bad weather.
The yurt is now probably more draft-free than any house I’ve ever lived in. It’s a sea of calm and totally drama-free while the wind roars outside. It’s bone dry inside even in the heaviest downpours.
I think the project has been a success… even if it did take its toll on me! It has been tested under the most extreme of weather conditions.
There’s still a really unique bathroom to share with you!