Tim and I have been talking about the next wofati. He's asked me to draw some stuff up so we can work out the design. I think he said to go for 800 square feet for 0.8. So, of course, I went and made it twice that size.
Well, should be good enough for the first round of feedback anyway.
Dave, if I'm understanding you, sounds like there are a couple issues with that. First, all metal will eventually burn out. The temps inside one of these bad boys are just too hot for metal. Second, you need the riser to be insulative. You need something like perlite or rock wool involved in the riser to help the system draw and work correctly.
Some of the reasons Paul doesn't love using the galvanized tubes: first all the galvanizing burns off and sends green smoke out the end. Next the tubes turn into powder over time. You are left hoping that whatever other materials you used have been vitrified or hardened to the point that they can stand alone.
At any rate, I don't think 1/2" of straight clay will do the trick for you.
Thanks Allen, I don't feel incredibly confident in what I've done here. In a couple days I'll be able to report back. If I need to buy more supplies to make it work, it'll probably be bricks and rock wool like Paul suggested.
Paul, I figure it's not the best option, but I really don't want to buy more stuff if I can avoid it. I've got lot's more clay and perlite, some rope gasket, and lots of chicken wire. This might get me through the rest of the winter. In the meantime, we'll be working on better stuff!
Thanks for posting this Zach! I can't seem to download the model. It keeps giving me a skp.txt file instead of just a sketchup file. Maybe the files I've been attaching are doing the same thing? I'm not real computer savvy in this regard. Any thoughts?
As far as what I can tell from the picture you have nailed the concept in your model. The cistern is a little bit further downhill, but that's a pretty minor detail. It also looks to me that the proportions are off a bit, if the trench is actually 3 meters deep on the near side then it is a little too wide and the pipe too big. But again these are minor details. The only big thing is that in addition to the lengthwise slot pipe coming towards view from the cistern feed line, there is another just as long, going away from view. Great work Jesse! You really nailed the concept, if you attach the model I'm happy to review it in more detail and add my thoughts.
Zach, if you click on the image it should zoom you in a bit so you can read the text.
The proportions are definitely not to scale. I was using feet and inches so the pipe and trench are more visible.
So the slotted pipe runs something like 50 meters horizontally in both directions from the cistern pipe?
Zach, I've very much enjoyed reading the things you've been posting. This is something I want to really wrap my head around. Based on what I'm seeing above, I've come up with a digital model to try and understand better. Would you please take a look and help me fix it so it's more accurate?
Dave - I like the idea of using fiberglass, and if I understand right, roving is different in that it is woven? A material that offers tensile strength and can take the heat seems like a logical fit. fiberglass is something I haven't played with much so it'll take me a bit to figure out terminology, sources, and other details.
Cam Mitchell wrote:
So between pics 490 and 502, did you wait for the cob to set up some before hand-sculpting the manifold?
Or was it stiff enough when poured to do it?
Is there an internal mold for the manifold transition to the bench?
I was wondering why there were two sections of riser. Is this where the failure is?
Please, more details on the riser issue!
It seems like it dried overnight, but could have been sculpted right away. I ended up not really "pouring" so much as making baseball sized globs and mashing them together one at a time.
There was was no internal mold. I used a tape measure, large compass, filet knife, dry wall rasp, and my hands.
The two sections thing came about because I was trying to do a kind of mold and knew I could reach all the way to the bottom of a 16" section as opposed to a full 32". Also, 2 short sections were easier to move and place.
I think the failure had more to do with putting fire to things while they were still VERY wet (got excited, and impatient), as well as not providing any kind of tensile strength reinforcing. I'll be posting pics of the damage probably when I can show what I've done to try and fix things.
While talking to Paul, he seemed to think that I'll need to do something totally different with the riser. I know they're using some pretty pricy and fancy risers at the lab that work really well. I want to continue to try and come up with something cheaper though it will probably lead to more failures and frustration and I'm ok with that.
There were folks here 2 days ago helping me get things buttoned up. The system is still quite cold and wet and I think some optimization needs to happen, but we did burn a fire in it for about 1/2 an hour. Here are some pics of what happened over the weekend.
You'll notice there's a "fancy" corrugated metal roof wall behind the bench. while looking for the cheapest metal roofing I could find for shelter in my chicken paddocks, I decided 50 cents a square foot was a great price for a finish material and might help me achieve the man cave ambience I'm going for. Also, I figured if I didn't get that bit of the wall finished in some way, there was a real good chance it would NEVER get finished.
Some thoughts... I live in suburbia (in an HOA even). I've posted this publicly here and in a couple facebook groups. Some people I don't know yet are coming to help me work on it in a few days. I figure it's a matter of time before "bad guys" get wind of what I've done. If I can just get enough time to compare heating bills before and after + prove that it's completely clean and safe + make it "pinterestable", I might have a fighting chance. Other people might even want to do something similar. Probably not, but maybe. A guy can dream right?
A.J. Gentry wrote:I am very happy to locate this thread as I am really trying to picture what a hugel / swale cold climate set up would look like. I was just listening to one of the podcasts -- #228. Paul and Geoff Lawton are talking swales. Size and depth. And I think they chat on / off contour (maybe not). I wrote down that Paul said 8 - 12 inch depth for the swale in a cold climate. But I don't know if that was for on contour or off... or both.
I will post my specifics --
Slope is 10 - 15 degrees from NW to SE
Average annual temperature 52.8 F
Average annual rainfall is 39.4 inches. With 27.7 inches of snow. (I admit I am not sure how to locate how much of this falls during the growing season.)
I have not put the beds in yet, but if they run N-S they would be 200'. If they run E-W they would be 60'. (E-W would be contour) These would be pretty tall. The land has a lot of rotten wood from old trees. So maybe 4-5' tall.
I guess my two main questions are (1) Does the bottom of the swale butt up against wood or soil? (I hope this makes sense or that I can explain better). Let's say I put in a swale E-W. I take my shovel and start to dig the swale at 12'' deep. Would I dig another trench (down slope) to toss the logs in then cover? OR do I dig my 12'' swale and put the wood (again down slope) on top of the soil? I was thinking in order for the wicking action of the hugel to work the water would have to have access to the decaying material. Most of my soil is clayey loam.
(2) Is there a way to both capture the water and let the cold run run downhill? These two things seems mutually exclusive to me. (Again a concept that is tough for me to visualize). If I were letting the cold air go wouldn't that mean I was off contour and therefore wouldn't be able to hold water? Should I even worry about water because of the rainfall in my area? Because of the size of the hugels and once they are in place for 2 years I won't have to worry about it anyway?
Once upon a time I started to breach this topic with Paul and he began to pull out his podcast recording apparatus and I got stage fright and declined participation. That means a few things. One, I am partially to blame for not having more of Paul's thoughts on this topic in podcast form. Two, I still don't know what he might have said since that was the end of the discussion. And three, I feel like I should try to participate in the convo now if only to interject my best guesses.
Right away, that looks like A LOT of precipitation so I'm thinking swales aren't needed to hydrate your landscape. One of the things I've noticed in my limited experimentation is that decompaction is a major benefit to the soil when creating swales. That said, making hugels will also decompact.
While watching the Agro Rebel, I was looking hard for on/off contour stuff on Sepp's place. I noticed that there are places where hugels appear to be laying perpendicular to contour, and places with mounds that look more like lots of lumps in a pattern resembling moguls on a ski slope.
There are also, of course, 72 ponds (shallow and deep) tucked all over the place that are linked more to contour. I think the major take-away is lots and lots of diversity in micro climate creation.
One of Paul's things is TEFA or Textured Earth Food All-year. He seems to purposely leave this vague. Just add lots and lots of texture. In my mind, that means something like do lots of experiments. Do lumpy stuff all over the place big and small, on and off contour, wood buried deep and wood higher up, wet and dry spots, hot and cold places, and plant all kinds of stuff and see what happens. Lots of edge. Work animal paddocks into it all somehow. It's hard to get into that patient kind of mind set but could be incredibly liberating. Do whatever the hell you want to see. You can always tweak it or do something totally different. Observe and interact.
As far as I can tell there still remain these two immutable rules lest you reap the Wheaton whirlwind :
DON'T TRAP FROST
DON'T DRY OUT YOUR HUGEL BEDS BY HAVING STICKS POKING OUT OF THEM (unless those sticks are "nails" holding down deep mulch)