Oehler PSP / WOFATI type homestead project

This is my first post to Permies. I have really learned a lot and enjoy the hell out of this forum. Lots of great info and like-minded people... very cool.

I just purchased 1.5 acres outside of city limits here in Arkansas. There's no building codes so I'm good to go. As of now the land is rough and overgrown but I will begin clearing it next week. There are 2 small creeks and LOTS of eastern cedar/ juniper on the property which I will be using for pretty much everything possible. This will be an ongoing thread documenting the process , as well as where I will post my questions that I have for all of you resourceful people here on permies. I'm a pretty resourceful person myself and have done tons of research but there will be plenty of things that I will work out as I go. Here is the plan thus far.

-Oehler/ wofati type structure built from cedar/juniper from the site
-Off grid
-Design based off of grid of posts 8 feet apart
-The property is fairly flat so this will be an earth berm type structure using as much soil as I can from the site, some of which will be excavated from pond(s).
-Gabled partially on the north side with a few windows, 40- 50% southern surface covered with windows for solar gain
-Rainwater and/or creek water harvesting and filtration using (probably) deep sand with UV filtration for at least the drinking water, possibly solar or boiler still for other water. (still working this out)
-Waterless compost toilet
-Greywater system with reed bed filtration running into a series of small ponds/ pools / reservoirs
-Rocket Mass Heater
-Attached greenhouse
-Earth Tubes for additional cooling in summer. We have very high humidity here during the summer so a natural dehumidification system will be in order. I'm not totally sure that this will be necessary or even a good idea due to the high humidity of Arkansas. If I do proceed with a small earth tube system, drainage and dehumidification will be serious issues. Dehumidification would be via calcium and or salt type dessicant. This would be an active system with 3 small fans pulling air through filters into the west side of the house and a exhaust fan on the eastern side.
- Wood gasifier with natural gas or propane backup used to run generator a couple hours a day to charge batteries. (System designed for low power consumption. Generator will be housed for low noise with automotive muffler attached for extremely quite operation


One question that I have is in regards to rainwater catchment and a green roof. Originally the shed roof was intended to slope down from south to north. I was considering some type of gutter/ french drain type setup on the edge of the roof, above the top layer of polyethylene to capture rainwater. Not sure if this would work. I'm also considering changing the slope from north being the high point and the south the low point with a regular gutter rainwater system. This whole entire concept may be full of problems as I have been unable to find anyone doing anything similar to this. Obviously the green roof presents issues for rain catchment . I do intend to construct a series of small reservoirs where I can divert creek water to and then I could pump that into the house water filter system possibly as the entire water source or at least as a backup.

I am also still working out what I want to do with the flooring. I am considering putting a thin subfloor over the moisture barrier and laying wood decking over that so I can have tile or vinyl in the kitchen/dining area. I'm not sure if I want to put carpet padding and carpet directly on the moisture barrier oehler style. Seems like it would be easy to puncture the moisture barrier by dropping something. I guess I could just cover the moisture barrier with some felt and dirt and then lay the carpet directly on that. (?)

Does anyone have any views on the earth tube and dehumidification system?

I also wonder about the shed roof slope. The structure will be 40 feet wide by 32 feet deep. I know a typical flat roof allows for 1/4 inch of slope per 12 inches. This comes to 8 inches across 32 feet. I don't think I feel comfortable with that number. I was think more like 12-24 inches of drop across 32 feet. Any input on this?

That's all I can think of for now, any insight is greatly appreciated!

Would it be a better idea to post my individual questions in separate threads?

Another question related to Oehler structures in general, and I suppose this isn't a problem since Mike's original structure didn't seem to have this issue: Why does the weight of the roof not drive the poles deeper and deeper into the ground?

Whoa. Sounds really cool. Do you think you can implement/install most of these things on your own? I want to build my house much like yours, and if you need some free labor I'd be happy to help as long as I got some knowledge out of it. Especially with the Wofati, I'd like to see a couple put up before I try and do it myself.

jesse markowitz wrote:Whoa. Sounds really cool. Do you think you can implement/install most of these things on your own? I want to build my house much like yours, and if you need some free labor I'd be happy to help as long as I got some knowledge out of it. Especially with the Wofati, I'd like to see a couple put up before I try and do it myself.

Jesse, yes I do think I can implement and install pretty much everything on my own. I have several friends that will be helping out also. Where are you located at? I have a significant amount of land clearing before I start building. Gonna start this project tomorrow.

I broke ground today. 2 friends and myself were able to clear a significant section in a couple of hours with a chainsaw and loppers. Helluva brush pile already. I'll post before and after pics tomorrow most likely.

Also, I think I have figured out what I will do with the floor.... compressed and sealed earth blocks. Looks really good, easy to maintain, and adds thermal mass.

http://makeprojects.com/Project/Cheap-and-Easy-Earth-Block-Floors/759/1

Steve Wylde wrote:Another question related to Oehler structures in general, and I suppose this isn't a problem since Mike's original structure didn't seem to have this issue: Why does the weight of the roof not drive the poles deeper and deeper into the ground?

Because they are big enough to act as their own footers, pressing into undisturbed soil.

CEB earthen floors are cool, but earthen concrete floors are way easier. Next house will be a mix of earthen concrete and recycled brick (for the high traffic areas). I would rather spend the time it would take to make CEB's on food production.

Here's the first photos on the project. 2 friends and myself cleared a pretty good chunk with a chainsaw in 2.5 hours.

I've decided against trying to integrate a green roof rainwater system. I intend to build a shed and collect rainwater from there, as well as pumping water from the creeks into a filtration system, possibly a sand filter and solar still. I think I'm just going to do the part of the floor that gets sun exposure in linoleum and the rest in carpet. Not 100 percent set on this yet. I've cleared out a lot more undergrowth and will post pics soon.

Well the underbrush has all been cleaned out for a large area around the construction area. Now it's time to start felling large trees . The area is actually bigger than I could capture with my camera. Driveway is going in soon.

progress?

I have been steady working out there. I've got the driveway in, cleared more tree and have been setting up the temporary power for the travel trailer I will be living in while I build. My phone has been taking crappy pics lately but I'll see if I can get some decent pics tonight. Still hard at it!

Well I tried to post a fairly lengthy update the other day but my browser screwed up and I lost the whole thing. I was not a happy camper.

I have power set up and have officially moved into my travel trailer on the land. I have been using a sawdust compost toilet like the one from the humanurehandbook.com site. Simple and effective, and odorless. The only problem is I have to buy pine shavings for cover material. It's only about 5 bucks a month but the damn stuff has fruit fly eggs in it. I use little homemade apple cider vinegar traps with dish liquid in them and they do great and take care of the vast majority of them. I wish I had an alternative though.

Now that the weather has cooled off I will be able to get a lot more done. Still have to cut down some more trees then burn the brush piles or rent a chipper. I have been using a flojet demand pump hooked up to a 275 gallon ibc tote for water. My friend lives down the road and I have another tank that I have taken to his house a couple times to fill up and then drain into my tank. It's surprising how little water I use without a regular toilet. 250 gallons will last about 3 weeks. I have found an unused well 2 feet from my property line and 30 feet from my trailer and the neighbor said I can use it so I am in the process of getting that set up. I am needing to build a well house around the storage tank and where I will mount the jet pump so I posted a question in this thread:

https://permies.com/t/18055/homestead/Ideas-cheap-well-house#154468

I have also decided that an earthsheltered earthbag house may be easier and cheaper for me to do so I think I will go that route. The soil on site seems to be ok for earthbags and I can do a lot of the work by myself when necessary. I still plan to use the PAHS umbrella. At this point I am thinking about starting with building a living room / bedroom section that butts up next to my travel trailer so I can still use that space. I'll have a carport over the trailer to protect it from the elements and use it to collect rainwater. At this point I intend to use Owen Geiger's "Earth Lodge" plans and build modularly in sections no bigger than 800 square feet at a time though the first section would be more like 400.

We have fairly frequent tornadoes around here and I'd like to be partially earth-bermed at the very least. Are above ground earthbag homes tornado proof?

My initial inspiration for this project was Simon Dale's hobbit house. I love the way it looks. He uses strawbales under soil which is supposedly a no-no. Does anyone have any input as to why I should use PSP or strawbale instead of earthbags? Should I change the title of this thread or should I start a different thread for this project since I'm leaning away from PSP at this time? Any other feedback?

hello Steve, i havefound that ,like Mike Ohler, plastic sheeting will work well underground if done in such a manner that joints are glued or lapped so that static pressure from lengthy rains cannot get past it, i put up pictures of my lowcost system a while back and dont know how to pull them up at this time,it is a round dome utilizing full trees and adobe/cob, plastic sheeting has been recognized in the building trade as a excellent waterproofing since it was invented

Yes I had planned on using polyethylene sheeting anywhere that would be underground. I was planning on using lapping per Oehler's standards. Is there a glue that works good? I also intend on using the PAHS umbrellla and swales so that water won't be anywhere near the house anyway.

I found a couple posts you were referring to:

https://permies.com/t/12657/cob/Underground-cob-house

https://permies.com/t/13536/green-building/Building-Material-Technique-South-Carolina

Do you have any heating or cooling sources? How cool does it stay in the summer and how warm in the winter? How large is the structure and how much did it cost you to build?

The pictures are very small. Any way you could start a new thread explaining what you did and all about your structure and bigger pics so myself and others can have a look? It's very interesting.

My property only has a very slight grade. I am still interested in exploring other building techniques and I'm wondering if totally earthsheltered or partial earthberming is the way to go. We have very hot, humid summers here and pretty damn cold winters. I had planned on having a dehumidification system but no central heat or air.

Steve the carpet/tile glue works good, it doesnt melt the plastic, The Passive Solar Energy Book written by architect Edward Masria ,1979 is chock full of info on passive solar. air movement is key in earthbermed housing, by Code treated lumber and treated plywood with plastic vapor barrier can be used underground for several years now

Good project, Steve!
Yes, a bit more slope on the roof would feel more secure. Maybe some south-facing clererstory windows if you need to break up the roof line into two shed roofs. These work fabulously well for cooling on summer nights and will let in low-angle winter sun.

http://www.australiansustainablehomes.com.au/FAQRetrieve.aspx?ID=34048

For making the seams in the builders' plastic I used acoustic tile cement along something like a 'flat felled seam.' Only you are not sewing, but spreading this goop on. You glue the two edges, fold, glue again, fold. So you wind up with a seam something like the seams on your jeans only much bigger and without stitches.

Alternatively, you could use butyl rubber roofing or pond liner instead of PVC sheeting. Costs more, but more durable.

Check out this house.
http://www.countryplans.com/underground.html
Lots of good ideas! Here is the goofy, but instructive, video of the house:
http://www.youtube.com/watch?v=_pJwx-DqnI4&feature=digest (Is that Mike Oehler with the mask?)

There are so many ways to do things. Sounds like you have an excellent plan.
Maura

R Scott wrote:

CEB earthen floors are cool, but earthen concrete floors are way easier. Next house will be a mix of earthen concrete and recycled brick (for the high traffic areas). I would rather spend the time it would take to make CEB's on food production.

I've done several floors of both types (I am the author of the above-mentioned CEB article), and I tell ya, there is nothing easier than CEB floors. I bought my CEBs, but you might have other bricks available in your area for free or cheap. Any brick will work fine, and it saves a lot of time and labor compared to concrete-type floors. Bricks also have the advantage of coming out good, even for the beginner. Concrete-type floors, especially made by beginners, are prone to a lot of issues.

Instead of poly sheeting, you might consider vinyl billboard tarps. They can be found cheap or free in a lot of areas, and are a lot more durable than poly.

Steve, any news on your project? I'm in central Arkansas too.