How To Redesign A Fallen Earthbag Wall
78The Blessing Of The Wind
The near hurricane force wind that knocked down two walls of our earthbag home-to-be on December 6 is documented in Sarah Palin, Soldiers, And Earthbag Walls. What that article does not define is the immense benefit which accompanied the apparent destruction.
Two weeks after the fact, the rebuilding and improvement of the walls is complete. It could have happened more quickly, but five of those fourteen days were spent dealing with my wife's medical needs. No complaining, just explaining.
One thing that I'd failed to include the first time around was a hole through the wall suitable for a possible future dryer vent. So that was corrected by inserting a piece of four inch black ABS pipe with caps at either end.
Redesigning The Walls
Originally, the plan was to add short pieces of planking above the window framing, then pile on another three rows of earthbags to top things out. Above all of that, then, partially filled earthbags would be juggled to level things out...and two layers of planking would then be applied, forming the base for adding the premanufactured trusses (now on order).
But.
Since two walls (and later a portion of a third wall) had hit the ground, making sure it never happened again seemed pretty obviously the order of the day. Temporary bracing was applied to the walls that had held, and that bracing will stay in place until the trusses and a powerfully supportive interior studwall are fully installed. To firm up all four walls, I figured (at first) that I'd have to:
1. Run a row of planking all the way around the wall tops at the above-the-windows level, complete with installation of twelve inch spikes to serve as "poor man's rebar", securing the walls from further destruction.
2. Add three rows of earthbags above the planking.
3. Construct the top beam as originally planned.
It didn't take long to see that would go plumb beyond being ignorant into being purely stupid. The plank-and-spike addition to the wall tops did secure them nicely, or at least one heck of a lot better than nothing. On the other hand, it proved absolutely impossible to make those planks come out completely level. Some were warped a bit to begin with, but the primary problem involved the underlying earthbags. Simply put, bags of dirt aren't exactly framing lumber. If I'd gone with Plan One, no way under God's blue sky would I have been able to construct a stable platform to underlie the roof structure.
Thankfully, Plan B wasn't hard to figure: By switching the last foot of height to a frame structure, I could easily enough produce that all-important level, stable, wooden base upon which to mount the roof trusses.
Topping The Earthbags With A Row Of Planking
Framing The Top End
Although the pre-truss framing will require a separate article, it seemed worth showing just a "touch" of that on this page. My wife tells me she was entirely unable to imagine what I was talking about it until she saw the planks being put in place.
So...here y'go, until next time.
Update: March 22, 2011
We've been living in the completed home since June of 2010, but this page wouldn't tell you that...until now. When things were ready to stucco, it took exactly two weeks to do that job. Now we call our place the Border Fort, able to stand strong against any potential attacker from future big winds to bullets from an AK-47 rifle. The walls won't ever fall down again, regardless of the provocation.
Guaranteed.
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Thanks, Nelle. Additional updates and pics will follow as the project progresses. We weren't anywhere near the walls when they blew down, so no, nobody got hurt. Only things hurt were the earthbags themselves (fallen soldiers!)...and of course my otherwise healthy ego.
Ghost, I'm thrilled to see almost everything back in place! I've been praying for your work on this project, and am glad to know things seem to be going right.
Thanks, Joy. Appreciate the praying, too. My next Hub on the project will show the framing above the earthbags which will set things up for the roof trusses.
Hi Ghost,
Now that I understand what your intentions were with the double 2X "bond beam" and the 12" spikes, along with the intertied interior walls, the whole plan seems more inherently stable than it did at first, and I'm sure that it will be plenty strong over time.
I am glad to hear that you have decided to suspend with the tar paper lining. I was a bit concerned that it would tend to weaken the wall, since the stucco plaster would not be integrally connected with the bags. With the plaster penetrating directly into the crevasses of the bag wall, you will have a much more monolithic structure. It should also breathe better, even with the paint protecting the poly material.
Thanks for the go-ahead to post your project at www.earthbagbuilding.com. I'll wait to do so until you are somewhat further along with the project, and let you know when I do.
Sounds good, Kelly. The next article (covering the top-framing) should hit publication somewhere within the next ten days--the good Lord willing and the crick don't rise, of course. Then the interior bearing wall, and then the trusses.
I'd been mix-minded about that tarpaper myself. Cutting it out of the equation wasn't a hard decision.
Now if I can keep Pam (my wife) calmed down about that "ugly mint green paint" (not yet shown) until time to stucco, we'll have a winner!
ghost
i don't understand why you could not have continued laying three or four more courses of bags above the tops of the windows, then install a belt column (bond beam) on top of that and then install your roof trusses.
the planks you have on top of wall sit directly on earthbags. the framing upon which your trusses will sit is on top of the planks. will the earthbags continue to support the framing without shifting somewhere along the line. what i mean is, can the equilibrium above the bags be upset by earthbags shifting since bags are filled with dirt and are not solid?
i apologize in advance for my ignorance. i appreciate your patience.
sylvia
No ignorance involved in your questions, Sylvia. They're all solid queries.
Something I probably should explain is that I have a particular talent. If I focus clearly and carefully, I'm able to literally SENSE ALL OF THE FORCES working for and/or against anything at any time. Example: I've balanced a car on a very unstable jack and done work--such as changing a tire--without ever getting hurt except once when I was 16 and didn't focus. Other people would be at risk, but I'm not.
The walls fell originally because I HAD NOT APPLIED my force-sensing ability to its fullest.
That said, I also tend to "intuit" what will work best and what won't in many, many situations. In this one, yes, I could well have done as you say, finish out the bags and then go to a bond beam. I chose not to do that because I'd discovered by experience (running the planking all the way around) that it's IMPOSSIBLE to get 144 running feet (i.e. 4 walls of a 36 foot square home) of planking completely square and level when putting them directly onto the bags.
So I "doubled up", as the last photo shows.
The top-framing reasoning is discussed in the forthcoming Hub on that specific topic, but here's an outline of the reasons why I'm doing what I'm doing:
1. The 13 levels of bags that are in place were simply not stable at all. Adding three or four more prior to topping out earthwise would have been like wrestling a slimy, slippery octopus. Maybe a squid.
2. By "box framing" the short (11 to 13 inch tall) studwall, I added an incredible amount of stability to the entire structure immediately. I have the east and west walls done now, and though I'm leaving braces in place "just in case", I really doubt any bracing at all is necessary where the top-framing has been completed.
3. By cutting the bottoms of the short studs on premeasured angles, I'm able to take a crooked, twisty plank (the one directly on the bags), go up to the desired final height, and produce a flat, level, stable surface on which to mount the trusses.
4. These earthbags WILL NOT SHIFT. They ARE solid and stay that way. Between the barbed wire holding layer to layer, twelve inch spikes down through the first plank and through 2 layers of bags, the intertied interior wall I'll be adding, the exterior stucco, and the completely hurricane-tied roof system, the final structure will be as solid as the Rock of Gibraltar.
If wind can't push a wall IN, it can't knock the wall DOWN. When all is said and done, we'll have a virtual fortress. On top of that, the "feel" of having 6 feet of thermal mass (earthbags) topped by a heavily insulated (R-30 plus airspace plus R-ll) "cap", my gut is telling me we'll have the best of all possible worlds.
Naturally, we do have to wait and see.
Wow, this is quite a task. I am anxious to see how it progresses. I'm relatively new to sustainable housing options, and I find your project fascenating. Am looking forward to your updates!
Thanks, Relica. The next update should be available in another week to ten days, certainly by mid-January 2010.
I am really enjoying your postings on the earth house. I build and have learned a bit over they years. May i subjest a few things. Build some interior walls that deflect wind forces on the main walls while building the structure. They need be no longer then the exterior wall is tall. And they need to butt to the exterior wall. Place them no futher apart then 1 1/2 times the exterior wall height. They could be sandbag walls. As with most buildings people try to build long walls and the wind will always be a problem. I noticed your exterior walls are all flat run. This actually weakens a system. Insets in walls creat strength for wind resistence. That is when i always try to use a few insets when building. Wind is always a issue. But great job on the house so far. Good luck i will be watching and learning.
Thanks, "I build things too". Your suggestions are solid, but for this structure just slightly after the fact. In other words, the shell of the house is DONE, as perhaps best summarized here:
http://hubpages.com/hub/How-To-Build-A-House-Singl
I was aware of the value of insets but way too stubborn to use them--they would take time and materials to build, time to remove, and I just couldn't get myself to take the idea seriously. So I did a "poor man's inset" version of the same concept, i.e. lots of temporary bracing.
There was one section in particular that was vulnerable to caving in, so as soon as the trusses were in place, a bit of interior stud wall was added to make sure that wouldn't happen. Those studs were strongly anchored to the trusses themselves; that wall CAN'T fall toward the interior now.
Eventually, there will be a top-and-bottom-anchored stud wall all the way around the interior perimeter. But even as it stands today (04/04/10), the walls will withstand truly ferocious winds. In fact, they've already done so.
But again, thanks for our concern.
Wow reading your notes on your project has put a smile on my face,almost teareyed. in looking at your pics. it seems the bags are round instead of laying flat after the tamping process that I highly recomend. also the lack of using butress on corners and at least every 18 feet or so would have saved alot of trouble and possible ingury after watching your project Im sure alot of people have changed ther minds about building a earth bag home
Thanks for checking in, Rob. A few responses:
1. The photos may be fooling you. The sides of the bags are rounded, but tops and bottoms are flat--each back was whack-tamped with a 30-inch chunk of 2"x12" planking. On average, the whacked bag measures 5" high by 11" wide and 17" long (give or take). Roughly 8" of the 11" width is flat, leaving 1 12" of "round" depth on each side of the bag.
2. Based on my experience in building this house (the first and only such to date), the corners automatically buttressed themselves. One or two additional buttress walls per side could have proved useful, but I had several reasons for not including them, to wit: Building them would have been (in my book) a real pain, would have slowed down the process,would have required more bags and barbed wire, stucco and paint, and would have provided a dangerous hiding place for any potential attackers in the future. (That last may sound paranoid, but when you live within a mile of the Mexican border, it's not something to ignore.)
3. Once the project was fully completed with interior 2"x4" stud walls anchored to both the roof trusses and the perimeter foundation concrete blocks, there was literally no possible way for the walls to fall down again...ever.
4. The addition of the concrete stucco was the final touch of structural strength; that turned the place into a literal fort. The stucco is a good inch thick (three layer system, applied with a hand trowel) over the widest bag rounds, swooping in to an average of 2 1/2" thick in the "cracks" between bags. It would take a tank to breach these walls now; a normal passenger vehicle definitly couldn't do it.
5. Saving trouble is a good thing, but all I needed to do to avoid that was a bit of bracing. I'd failed to check the forecast, had no idea the wind was coming, and...screwed up. No big.
6. Injury? Not unless the walls fell on us while we were living in the home, and that literally can't happen.
7. I don't know of anyone who actually changed his/her mind after checking out this project, but several people have thanked me for ideas they got from reading pages like this one.
8. Having gone through one summer, one fall, one winter, and now moving well toward spring, it looks like the earthbag thermal mass will keep us totally comfortable without either heat or cooling for about 6 months out of the year. In midsummer, I'd be fine with maybe a fan at most; Pam can get by with a fan but would be grateful to see some air onditioning. I installed a ventless propane heater, blue flame, 20,000 btu--designed (supposedly) for supplemental heat only--but it does the trick for the whole house, and the only time it ran excessively (nearly full time) was during one cold snap that took our temps down to 7 degrees Fahrenheit and hundreds (if not thousands) of water pipes in the area.
Even then we didn't get cold; inside temp never went below 70 degrees.
I'm glad to see your project was a complete success the final pics look very nice and I'm sure it is a very comfortable home. I can under stand your not wonting to make a hidding place for unwonted visitors w/buttresses I've had that same thought myself where I'm going to build at on one of the local res. You've got a fan!
Cool! Fans are good!
HOW IS THE FLOOR? DID YOU END UP USING A EARTH FLOOR OR CONCRETE? ALSO THE PLASTER OR STUCCO LOOKS NICE. BY THE WAY ARE THER ANY DEER IN YOUR NECK OF THE WOODS? THEYE ARE TASTY CRITTERS!
Floor: Concrete was not an option for two reasons. One, the expense factor. Two, Pam's health--especially the danger from falls on hard stuff.
The floor is actually simplicity itself:
1. Dirt, leveled with nothing but a screed board and tamped a bit with a 10-pound tamper. Nothing drastic.
2. Then a layer of 6 mil black plastic from Home Depot to serve as a barrier to both dust and moisture.
3. Next, a layer of OSB strand boards--which I used everywhere, as a matter of fact. Floors. Interior walls. Roof sheathing.
4. Finished off with 3/8" interlocking rubber floor tiles made from recycled tires, the sort of flooring you often see in, say, weight pumping gymnasiums.
Every bit of every layer is strictly loose lay. Beatiful result, plenty of "give" underfoot, easy to clean. Did come up short about 10 tiles to finish the final room, so the kitchen has some square footage where we're still "walking on wood" until finances improve (which they should, later this year).
Deer: Yep, we've got whitetail. I gave up hunting more than 40 years ago, though, and Pam will cook venison for others to eat but won't consume a bite her own self. Bambi Syndrome.
THE RUBBER FLOOR IS A GREET IDEA! BET IT STAYS WARM
I HOPE YOUR WIFE IS FEELING BETTER. BE COOL BRO
Pam's doing well this a.m.; thanks for the good thoughts.
Yeah, we like the rubber floor a lot. You're right; it doesn't get cold, just stays slightly cool in summer and winter both--but not cool enough to be uncomfortable to a bare foot. Couldn't ask for better.
It also allows plenty of headroom (seven feet, four inches) while keeping a low profile for the overall house--which is good for slipping wind a bit, minimizing the amount of building materials that had to be purchased, and even for defense if the house ever actually has to serve as a fighting fort. The three flooring layers (plastic plus wood plus rubber) only take up 7/8" of height above the Earth itself.
Nelle Hoxie 2 years ago
I hope you'll give us more pictures and updates. This is a fascinating project. I hope you both were unhurt during the near hurricane winds. That must have been very scary.