• Post Reply Bookmark Topic Watch Topic
  • New Topic
permaculture forums growies critters building homesteading energy monies kitchen purity ungarbage community wilderness fiber arts art permaculture artisans regional education experiences global resources the cider press projects digital market permies.com private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Nicole Alderman
  • r ranson
  • Anne Miller
  • paul wheaton
stewards:
  • Mike Jay
  • Jocelyn Campbell
  • Miles Flansburg
garden masters:
  • Dan Boone
  • Dave Burton
  • Steve Thorn
  • Greg Martin
gardeners:
  • Shawn Klassen-Koop
  • Pearl Sutton
  • Mike Barkley

Wofati build finally started

 
Posts: 98
9
  • Likes 3
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hello everyone,

We started our build today on our Wofati!!!

Well kind of started lol.  After many drawings, reading and years of research were 3D printing our wofati timber frame and will be assembling soon.  Need to see my design to prove it.   Once that’s completed and the frost out of the ground we will start digging post holes and finish milling our lumber!

I’ll try my best to keep our build updated, please chim in any time with better ideas and such.

Please stay tuned for the model build and official ground braking!!!

Current details
Main frame footprint 48x32
Insulated umbrella extending 20ft in all directions
8x8 timber frame
Post 8ft on centre
Got tons of used plastic from farmers throwing out it’s like 10m or something will be able to put multiple layers on the wood layer and over the insulated thermal mass
4” insulation tappers down to 1” on the thermal envelope
Building on flat ground


First order of business after the model is built and plans or final in my head...

Drill holes for posts
Throw posts in holes
Plumbing and electrical chase brought in
Bring gravel in tamp level posts bring floor grade up to meet satisfaction lol
Finish framing
Shoreing on walls and roof
Back fill the wofati

Enjoy my journey
Finally able to give back from my experience here
Byron

Sorry not good at sketch up yet
I’ll try and include a more detailed draft of the plans soon


image.jpg
[Thumbnail for image.jpg]
8x8 timbers on the mill
 
steward
Posts: 4127
Location: Northern WI (zone 4)
1029
books food preservation hunting solar trees woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I just watched a wofati video and one thing Paul mentions is that he wished he pounded his vertical posts down when he set them in place.  All the weight of the earthen roof has caused some to settle.

Another thing he mentions is that wofatis are best on sloped land.  I can't remember if that was a deal breaker or if it just reduced the amount of dirt that needs to be moved around.

This will be a cool build to watch!!!
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Yes thanks for that reminder about the pushing on the post with hoe if I remember correctly when Paul was saying.

Yep easier to move dirt uphill downhill onto the structure.  I’m digging a dug out no way around it it’s just going to be work.  Another detail is building the floor up above the grade of land in effort to keep dry during spring run off.

Cheers
Byron

 
Mike Jay
steward
Posts: 4127
Location: Northern WI (zone 4)
1029
books food preservation hunting solar trees woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Awesome, I'm glad you have it all thought through.  I don't know how many wofatis have been build outside of the lab so this will be neat.
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Here’s the water shed direction off the structure.  I think I got it right.  No drop sees a edge and always away from the structure.

Window placement.  Note the front windows facing directly south for most amount of thermal gain.  Two rear windows for bedroom light, ventilation in summer and egress.   The windows facing the centre mass or 8 ft off the grade allowing the centre drainage off the front of the structure to continue downhill to the rear of the building passing under the windows.   This area will need particular attention to insulation and vapour detail when building.   These two high windows will allow for a pile of light into the structure from different angles at the same time allowing the rest of the thermal mass to remain beefy and continues.

Beam detail how I plan on my timber frame to be payed out very affective I’m thing fast and easy.  Dealing with the inward pressure on the structure and downward pressure.  

Please rip these apart and tell me what’s wrong!  

Cheers Byron
40439DDA-3634-4D2A-A1CD-05C634DAAFF5.jpeg
[Thumbnail for 40439DDA-3634-4D2A-A1CD-05C634DAAFF5.jpeg]
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Correction on the beam detail drawing left beam connection is the one I’m aiming for max contact for inward and down ward pressure.

 
gardener
Posts: 2922
Location: Upstate NY, zone 5
124
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
That left edge joint configuration looks very solid. The central ones (not to scale I hope) need to have the notches in the beams as shallow as possible so you don't weaken the beams and have them split at the inside corner of the notch from the extreme downward load. If you are using roundwood, just flattening the bottoms of the beams to give 4-6" width of flat bearing surface should do it. If the beams are going to be squared, I would make the notches in the beam bottoms no more than an inch or so, just enough to positively place them at assembly. Once loaded, they will never slip in a million years.

The best central joint detail would have the beams resting on a ledge on the post, and lapping over the top to join them, similar to the edge joint; but this is distinctly more work than simply flattening the tops of the posts. I would do it myself if I were building such a structure. Flatten the post tops at the right level, then notch each side say 2" x 2", and notch the beams to fit. The beam cutting is no more complex than before.
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Yes ok great insight!

I’m doing 8x8 timbers.  I’ll adjust the beam to 7” thick over the post at the moment it’s 4”.  I understand know and should known that.  So easy to make adjustments know on paper lol.  I guess I could even leave it a full 8 and set it on top with couple log anchors securing it.  Then no structure on the beam will be comprised.

Trying to wrap my head around the connecting beam, possible for a diagram? I’ll reread and rethink it.  

Thanks so much
Byron
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Ok got it that’s strong as can be thanks for the detail!

image.jpg
[Thumbnail for image.jpg]
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I’ll be using 8x8 posts. 8ft in centre.
With 8x8 girders. From the main frame.
So each connection lap will be 4”x8” making for a great contact.  Then of course pinned together.
Revised sketch of post details
5168AC28-53B4-4974-BFB2-3C7060645E6D.jpeg
[Thumbnail for 5168AC28-53B4-4974-BFB2-3C7060645E6D.jpeg]
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Err I did it again the right joint is wrong lol

Tell me to turn right I’ll go left everytime lol
 
Glenn Herbert
gardener
Posts: 2922
Location: Upstate NY, zone 5
124
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
The south wall is at the top of the plan view, right? That is ideal for light capture and seasonal heating, but the back windows are not. Obviously you need windows in the bedrooms for light and egress, but I think this particular configuration will lose much more heat than the lighting benefit warrants. There will be a bit of winter morning sun in one bedroom and a bit of afternoon sun in the other, but windows high in the walls will maximize heat loss while giving minimal solar gain.Those windows don't benefit the lighting of the main space, either.

I think you would get just as good lighting from putting the windows at the outside corners of the bedrooms, facing north and east or west respectively, with small gables at each corner to shed the water off to the sides. This would have much less in the way of complex waterproofing joinery in the roof and sidewalls (no sidewalls at all), and less exposure of roof edges to lose heat.

How tall are you thinking of making the south wall? If the space is 16' deep to the back of the main space, a 21' south ceiling would let winter sun in to hit up to maybe 6' high at most of the back wall, so the earth mass in the center of the volume will not be fully useful for thermal storage. With the envelope simplified to a rectangle instead of a U, you could put a masonry and/or cob mass in a good heat capture and storage position while keeping it only around 4' high, and be able to use the top of it for something... lounge, plants,...

A rectangle would have more roof area, but considerably less sidewall area to waterproof and fortify.

I do see the feature of your roof layout having no slope longer than 16' or so from top to lower edge, so slope can be maintained without excessive height. I can think of ways to keep that feature with a rectangle, like melding a full hip roof with the south-facing shed so water drains east, west and north from the central ridge. The bedroom corners would be thus placed to easily divert water from windows at the corners to either side. This would give a large central area of high ceiling, which could be used for a balcony over a storage area or something.

 
Glenn Herbert
gardener
Posts: 2922
Location: Upstate NY, zone 5
124
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Yes, good joint details
 
Glenn Herbert
gardener
Posts: 2922
Location: Upstate NY, zone 5
124
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
It looks like you're in Canada... seriously cold climate? What is the subsoil like? Where is the water table? If it is not extremely well drained, I think you will have serious problems with groundwater unless you can trench away from the sides and the postholes to drain.

Subsoil average temperature is close to the average annual air temperature no matter where you are, and I would have some concern in Canada about trying to heat up that mass under the floor. It will always conduct downward to some degree, more if the soil is clayey, less if it is sandy.
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Yes the top of the plan is due south.

The front wall was going to be 12ft.  Sloping down to 8ft over the 16ft run.   According to my calculations winter sun will hit the back wall the shortest day.  As the sun is so low on the horizon, but we only get 4 hrs of it on the shortest day.  I’ll really benefit from fall and spring gains as the days get longer in feb through till end of May solar gain would be a premium then aug till October a lot of gain again.  The sun is right over top in the summer, that’s why the detail to the rear of the structure with high windows.

This gives me lots to chew on. So wonderful.

More details about my build is I’m in the far north Yukon Canada.  We’re very dry little snow long cold dark winters.  Shortest day 4hrs winters solstice.  Summer nearly 24 hours of light hot and dry.

I here you on the middle windows in my defence they won’t be very big like I did in my shop I’ll attach a pic.    I placed seven around to let in light high and low.

The bedroom windows were only going to be as big a necessary for proper egress.  Also special order quad pane.  Insulated bearm up to the bottom of the window here.  Was what I was thinking.  Any exposed surface would be detailed and insulated to the highest degree not really on a budget for those details pull out all the strings best thermal glazing and insulation for these parts.

In the summer the sun rises in the north and sets in the north compass bearing would be rises at 20degrees say and sets at 340 degrees.  During the day the sun would literally poor into the house through those little windows in the roof.  

Insulation would be 4” of foam over the structure and continue out 8-10 feet then down to 3” for 4-6 ft then 1” remaining out to make 20 ft.  As explain in John Haits book.

I plan on installing our wood cook stove inside the house hot water and cooking on which know is in our shop and heating it for the last 7 years.  

Im going for the mass not to be 100% no heat year round but to temper the stove spikes and to mediate the -40 winters here.    

Love the input back to the drawing board.

image.jpg
[Thumbnail for image.jpg]
High windows in the workshop bouncing light down off the white washed boards from my sawmill
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
To address your concerns about water.  We or on a old ancient lake bed.  Lots of sand great perk rate.  The only problem I have is standing water in the yard, after the initial thaw and the ground is still frozen in the spring.  Once the frost leaves the ground the water goes to and it’s a dust bowl again for the summer.  I’m digging and will continue a dug out dig this is designed to take excess spring run off and store it.  This is were I’m pulling my back fill from.  This dug out can be drained each fall and pumped on the field to help the grass winter better, then be ready for the spring thaw capture.

I also plan on bringing the floor level up in the wofati to the same as my shop slab as we never have a issue with water there.  I’m pretty sure of course don’t know for sure but with a detailed umbrella extending out 20 ft I feel confident the posts under ground will remain dry also.  If a carry my gravel layer out and water sneaking in under the umbrella will hit the gravel and perk down.  Frost in the wet soil on the wofati will cause and surface moisture to run away.  My biggest problem is getting rain to water the roof during the summer keeping the roof green.

Currently my shop has a 6” slab 46x26 uninsulated 8x8 log walls r40 blow in ceiling.  Heated with our cook stove only through the winter, my daughter is bare foot most of the winter.  I’m a true believer in thermal mass.  It’s working great in my shop.  We had -12c last night I cooked supper fire went out and  21c in the shop at 8pm by 8 am the shop was 17c.  A small fire and cook breaky brought the shop back up to 20.  

Thanks so much for the feed back and challenging? I’m already adapting the design accordingly!
Byron

 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Dug out to be finished excavated and piled on the wofati.  This years run has already perked down.  It’s going to be shaped to provide cooling and reflection for the solar panels and greenhouse attached to the shop.  Need to pigs in when done to line it and finish shaping for me after I get the dirt I need.  

Sawmill ready to start milling down the timbers and lumber for the build

As you can see still cold here and muddy.
B19343BD-75A8-4A5B-A697-BE92F3E88398.jpeg
[Thumbnail for B19343BD-75A8-4A5B-A697-BE92F3E88398.jpeg]
92B3A5B5-BD19-4E74-8A7E-09BFD47E5A10.jpeg
[Thumbnail for 92B3A5B5-BD19-4E74-8A7E-09BFD47E5A10.jpeg]
0A6E87AA-91ED-41EB-B12E-D40B23F5C40C.jpeg
[Thumbnail for 0A6E87AA-91ED-41EB-B12E-D40B23F5C40C.jpeg]
 
Glenn Herbert
gardener
Posts: 2922
Location: Upstate NY, zone 5
124
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Some ideas to think about. Compact envelope to minimize heat loss perimeter. With your short summers and long cold winters, I doubt you will store enough heat in the exterior mass to warm the interior, merely enough to temper heat loss. I would advise concentrating mass around the heat source, like an RMH or other form of masonry heater, so that the mass can be made really warm.

All low buried wall edges, and a minimum of tall exposed walls. Plenty of high windows for penetrating light, but you couldn't make full window walls 12' high or the heat would flow out. Put transom windows in the bedroom south walls to borrow light from the main space, in addition to the exterior windows. Every point in the bedrooms would have direct view out the windows.

Very simple roof detailing to minimize chances of leaks. I'm not sure what roof slope is best for an earth-sheltered roof like this, but it may be that 3:12 as shown is too steep to reliably keep the earth from slipping. The peak might want to be lower for a flatter, more stable roof covering while still draining positively. For conventional engineered earth-covered roofs, 1:12 is recommended as the maximum without special anchoring for the earth.
wofati-1.jpg
[Thumbnail for wofati-1.jpg]
plan view with roof lines
 
Mike Jay
steward
Posts: 4127
Location: Northern WI (zone 4)
1029
books food preservation hunting solar trees woodworking
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator

Glenn Herbert wrote:The best central joint detail would have the beams resting on a ledge on the post, and lapping over the top to join them, similar to the edge joint; but this is distinctly more work than simply flattening the tops of the posts. I would do it myself if I were building such a structure. Flatten the post tops at the right level, then notch each side say 2" x 2", and notch the beams to fit. The beam cutting is no more complex than before.



Glenn, is the joint detail you're talking about the same as the left one on the berm shed?
 
Glenn Herbert
gardener
Posts: 2922
Location: Upstate NY, zone 5
124
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Yep, that would be it.
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi Glenn,  thank you so much for the drawing!   If it’s cool with you could I steal the design.

I’ll need to sit down and work out how to best run the beams and girders.

Much agreement  with you about the thermal mass not totally heating he structure.  ? Is how much extra heat needed to make the interior comfortable?  I guess we will have to build it, live there for 3 years and see how thermal inertia stables out.  

Wood cook stove going to cook meals and heat water in the winter should help a lot keeping the mass charged.  I’m lucky to work from home so I’m around regardless the fire will be going during the day.

Do you think its beneficial to have a thermal mass heater central in the wofati.  Heating the mass and allowing it to radiate into wall mass.  I’m leaning towards just using the cookstove as the walls will capture any heat radiating off the stove directly to the mass.

Possibly a well thought out rocket stove using the pipe through the thermal mass wall or under the floor to charge the mass?  

I’m willing to throw it out there and build the structure and see how it goes, worst case I have a barn, a shop, or a garage that’s earth bermed and still a usable shelter.   I’m willing to experiment with anything here!

Thanks again for your help,
Byron

 
Glenn Herbert
gardener
Posts: 2922
Location: Upstate NY, zone 5
124
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I would be honored if you used the plan I posted; that's why I put it out there. Obviously all the internal arrangement is left up to you, as I don't know your personal needs and desires.

You could tweak the roofline to get a tall window wall all the way across, but this would significantly increase your winter heat loss both in exterior wall and subsurface near the south wall, and my feeling is that you would have a spacious main room without that, considering the central 12-14' ridge. You could put cozier use areas near the edges, and the main gathering area near the center, for a natural hierarchy.

My feeling on the beam/girder orientation would be to run the main beams horizontally (across the roof slopes), and the "rafters", poles or whatever, with the slope, so so that drainage if there is any will more naturally follow the slope rather than pooling in a divot between rafter logs. Of course if the envelope works correctly, water will never get near the actual structure.

I would want some experienced advice about the best roof slope; you want enough to drain reliably off the top membrane without pooling in irregularities, but not so much that the soil starts to slide downhill when waterlogged.
 
Byron Gagne
Posts: 98
9
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Ok still haven’t broke ground yet.  But I’m working on a agricultural grant to build my dig out / organic swimming pool.  I just found out I could get the a big portion of the dirt work paid for possibly by the ag branch.  Need to dump the dirt somewhere mmmm!

Sometimes blessings or in disguise.  As one of my meat bugs accidentally get knocked up and had piglets. Lol we called the vet and he says that there is funding for vet visits well I almost fell over!  

Further digging reveals funding for fences, irrigation, well drilling, dug out building.

Need to have a coffee with this ag guy.

Till I figure this out then I’ll start my build.

Been thinking about building wofati all over the yard know
Wofati wish list
Pig and chicken barn
Freezer and meat cooler
House of course

Maybe time to purchase my own excavator as they I could bill it out for the dug out build!
 
Mike Jay
steward
Posts: 4127
Location: Northern WI (zone 4)
1029
books food preservation hunting solar trees woodworking
  • Likes 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Awesome news!  After spending two weeks at Wheaton Labs and looking at the wofatis, it would be wonderful to see more of them built.  It seems the wofatis there were built in quick succession so the issues with the first one hadn't revealed themselves before the second one was built.  So now they have to fix both of them which is eating up time that could be spent refining the design further.  

Some issues to think about:
  • Some posts settled under the weight of the roof.  Pounding/pressing the posts in may be better than drilling holes.
  • Round wood joints on wall exteriors weren't filled with cob so it became mouse tunnels (between logs and innermost layer of plastic)
  • Too steep a roofline meant it was hard to keep soil on the roof or too much soil was added to remedy leading to too much weight


  • Getting an excavator sounds like an excellent idea!  When you're all done, you can probably sell it for 75+% of what you paid.  Maybe more if it's a charcoal fueled excavator
     
    And will you succeed? Yes you will indeed! (98 and 3/4 % guaranteed) - Seuss. tiny ad:
    All of the video from the Eat Your Dirt Summit
    https://permies.com/t/106759/video-Eat-Dirt-Summit
    • Post Reply Bookmark Topic Watch Topic
    • New Topic
    Boost this thread!