The Tires are Done!

And we ALMOST met our goal of finishing before the end of March.   As we neared the end of the tires, it was apparent that we had allowed the engineer to mess up the roof design badly.  He made the top two layers of tires filled with concrete.  He was afraid that the way the roof was originally drawn wouldn't be strong enough to actually hold the roof on. To compensate, he wanted two layers of concrete filled tires with 24 inch anchor bolts running up through them and connecting to the bond beam. Goodness!  Furthermore, as the roof steps back and to the north, the original plans had stacks of 2X12's to elevate the trusses.  The engineer wanted all of these stacks to be continuous lengths of 2X12. Ridiculous.  The extra cost would have been ridiculous too.

I couldn't imagine trying to level a course of tires that were completely filled with concrete.  Not to mention, how would I get anchor bolts into the tire below? Dumb. Yeah, the engineer was dumb, but mostly ME for letting him make such DUMB changes! I paid him to make the job more difficult!

Then we had a chance meeting with an Earthship owner/builder/designer.  We showed him our engineering disaster and he came up with a fantastic roof design.  Not only does it look like it will be much easier than the original blueprints, but it saved us pounding about 50 tires too!

Our big plastic cisterns are still giving us fits. I'm currently fretting about how to roof over them.  As you can see in the pictures, the tops of the cisterns are taller than the tirework.  We could do another row of tires on the cisterns, but I think I will try to find a way to put domes over the tops. Earthship Biotecture puts a dome roof on their "Huts" that might work.

In retrospect, we had a very good winter for building a house.  Most of the weekends were decent building weather...but not ALL of them!!  The problem with a big snow is that the "U's" make for great snow drifts, burying all of our tools.  Then the snow melts and turns the whole place to a muddy lake.  Thank heavens for spring---although we could still get snow.  In Colorado, you just never know.

This is going to be an interesting detail.  Building code requires an exit from the middle bedroom.  The other two rooms are fine because you can exit the building through both the east and the west.  We could have fought the building department and might have found a way around this.  I've heard of other projects that have gotten around it but this will someday be  our children's bedroom and the window will make it more safe. More of a pain now, but more safe.

The biggest problem is that in order to have a window here, there can't be dirt on the other side. Therefore, the room doesn't get the same thermal mass.  Furthermore, the window on the north side will radiate cold into the room, but not sunlight (heat).  This has been done before, of course, but I don't know how warm or cold the room will end up being.  I may stub a propane line into the room for backup heat.  We'll see!

Right now we are doing a little plumbing.  Usually folks wait for a roof  before plumbing, I suppose, but we will need water to mix concrete.  I thought we could do the first rough in, have some water delivered and go from there.  As soon as the water is delivered, we'll put up the bond beam then frame the roof.  Can't WAIT to have a roof!

What I Would Do Differently

In retrospect, we didn't do TOO bad getting the tires pounded. We spent more money than we had hoped to, and it took us longer than we wanted it too.  There are several things that we could have and should have done to reduce the amount of time and money spent on the tires.  No big surprises here, but we won't spend too much time kicking ourselves over these mistakes....there's too much else to do! 1. Earthship Volume I clearly tells you where to put the dirt around the tires. Yep.  They were right. I cringe when I think about the amount of time and money it cost us to wheelbarrow dirt from one big pile to the tires. Next time I'll pile the dirt right into the U's, very near the tires and worry about digging out the extra dirt later. 2.  In choosing tires, it is shown on the plans as well as in the books that one should use 16" tires on the bottom, 15" tires in the middle, and 14's on top. Tire sizes are much more complicated than this. I read about how someone had used all 235 75R 15's and it worked well.  I didn't realize that person had a tall earth cliff and used half as many tires as we did!  A 235 is a light truck/SUV tire, and is much more volumous than you might think!  We did the top course in 205's and 215's.  These tires went more than twice as fast.  Furthermore, the "How to" video says that a tire will swell up about an inch and a half.  We could get the 235's to swell twice that.  Next time I'll use 235's for the lower  four or five courses then switch to 225's, then 215's then 205's. 3.  We've probably paid 100 different people at different times to pound tires and move dirt.  It was pretty challenging to find people that were willing to work AND do a good job. We've had all kinds of workers too.  We had a crew of stone workers that couldn't lay stone because it was too cold.  They didn't speak English and they worked CRAZY hard.  They were too expensive to keep, and then it warmed up.  We hired a crew of high school kids that we didn't know, and they screwed around more than they worked. Plus we'd get a different set of kids each weekend, so we were constantly training people.  So much so that we'd forget who we told what to and inevitably someone would screw something up. Definitely not worth the money.   Finally we hired the daughter of a co-worker.  She brought out three of her friends, we trained them well and we finally had a crew that rocked. Next time I'll carefully select my employee's and look for qualifications like: Taking 5 Advanced Placement classes, Plays two different instruments in the school band, Involved in church youth group, Built homes on a Mission in Mexico, etc. (Huh, the "Honor" in "Honor Student" actually means hard working and dedicated....WHO KNEW! Thanks Melissa!!) If you are still reading, I suppose you are wondering what we did well...

What We Did Right

1.  We got all the same size tires.  WE didn't really do this one, we asked Dave at the Tire Broker to save them and he did.  They were fantastic.  They loaded the tires too, which probably saved us five trips.  Lacing tires is an art.  Having the same size tires made leveling pretty easy because they would swell to just about the same height.  In the cases when a stray 225 would get stuck in between the 235's it was pretty clear that we had made a good choice.  It was much easier to push the 225 off and start over than to try to pound it up to level. Even if you had to spend a week sorting and gathering tires, I think it would be worth the time. GET ALL THE SAME SIZE TIRES 2.  We knew that we wouldn't be able to do all the tires ourselves, and I'm glad we knew that.  I haven't pounded a tire in two weeks and my shoulders and elbows are still aching. There is no way around it, this is hard work. BE REALISTIC, KNOW YOUR LIMITATIONS 3.  Our original plan would have had us pounding tires last summer.  We didn't really consciously do this one either, but BOY are we glad we did this during the winter. On overcast days at 45 degrees, we'd work in a long sleeve shirt and be comfortable.  When the sun came out, so did the T shirts. (Of course when we stopped working we froze and put all the layers back on!) It would have been miserable in the July/August heat.  Lucky for us, it was a pretty mild winter and most of the weekends were perfect. TIME YOUR TIRES SEASONALLY 4.  Get as many FREE people involved as possible.  We had several "work parties" and invited everyone we know and a bunch of people that we didn't know.  Not only did we get a lot of work done this way, but we might have influenced people to think about the problems with conventional housing.  We even had some fun! GET VOLUNTEERS I'm sure there's more, I'll include it later!

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