Yes, it's all about the roof beams now! Since the tire wall and the concrete work are all done now, the only aspect of this year's construction that is still outstanding, are vigas to our reciprical roof. While this is without doubt the most exciting and interesting part of the entire build, it is also the one that is most challenging, physically as well as mentally.
Conceptualizing the Roof
What's a reciprical roof? It's one where each one of the beams is supporteed by the next one, while in turn supporting the one on the other side. Okay, I know, words hardly do jusice getting this idea across. But maybe you have tried this as a kid (or an adult for that matter): You stand in a circle close together, turn to one side, and then slowy descend at the same time, so you each sit on the knees of the person behind you. While you have to maintain some muscle tensions at first as you get into place, once everyone has settled down into the lap of someone else, everyone can relax. Your mere position is going to hold everybody up. This is also a frequently used model to illustrate cooperation and inter-connectedness. So it only makes sense to use the same design for the roof of our Permaculture Earthship Theater.
Playing with Models
Okay, so now that we sorta understood the concept, let's see how such a roof would actually look! The model designed for this purpose is made of a piece of cardboard resembling the bond beam we poured last week, and thirteen sticks (relatively straight, just like our actual beams) cut to exact length according to scale.
As you can see, each beam is supported by the one to its left, while carrying the one to its right. The result is a surprisingly stable structure, that is strong enough to carry even a big pot of coffee. Great! Let's move on to a bigger model.
In this "almost-life-size" model we're using these slender sticks to recreate the idea of a reciprical roof. Their size has nothing to do with our actual roof, we're just using what we have on site to illustrate the idea, and practice the application of such a structure. In the end, once the piece has slipped into place, the roof is strong enough for you to walk on.
The Real Deal
So, now that we've all understood the workings of reciprical roofs, all we have to do is apply the same principles to our thirteen roof beams: massive logs of Royal Palm trees, measuring over 70 meters (230 feet) in length, weighing somewhere around 200 kg (440 lbs) each!
We've had quite a bit of fun with them already, dragging them around the porperty, grinding the bark off, and then taking them to our neighbor's place, where they would be submerged in a boric acid sollution for four days, to make them less appealing to termites. Lifting one up so it could be tied to the truck was hard enough. Getting them into position on the roof is a whole different matter. Originally we were going to hire a back-hoe to do this for us, but under the current lockdown conditions that is completely out of the question. So it's entirely up to us five guys (and one gal), our strength and our wits, to get these logs up onto the roof. Things are gettin more exciting than they've ever been before!
Follow our Construction Adventure in This Series:
Talking About Logs
Pouring the Bond Beam
The Circle is Complete, We're Pouring Tomorrow
Starting The Long Finish
Concrete Plans and Concrete Actions
Earthship Build in the Time of Hive and Coronavirus
Machines Taking Over Work: The Day Everything Changed
Zome Building Workshop in Mazunte
The Ceremony of a Minka
Hay Pase, Got the Permit!
The Diverse Cars at Itínera
Waiting for the Man
An Impression of Hyperadobe in La Boquilla
Bending Rebar Like a Mexican
Working at Night for the Perfect Level
The Challenge of Scoring Tires
Creating Conditions to Work and Live
Previous series: A Theater on the Beach