Wow! What a great response. You people rock! There's no way we can print all the responses, but thanks to everyone who sent us ideas. We really appreciate it and found them all helpful. Here are the highlights:
Laura Huth of Champaign, Illinios tells us about her recent discovery of Flex Shake, made from recycled steel-belted tires w/an external layer or ground slate. The ground slate hides the tough steel/rubber layer and provides UV protection. It's availableat $165 for 100 sq. feet of roof coverage from www.flexshake.com.
Ulf Ellingsen of Norway gave us some good pointers on turf roofs. He writes: "The good news is that it has been done for centuries - and is still being used. The bad news is that the skill of the original way is as good as dead, while the new way includes the use of plastic sheets. In the old days birch bark was used to cover the wooden roof as a water repellent - before the turf was added. These days heavy duty, textured plastic surve the same pupose. The advantage of the plastic beeing that it is water proof - the disadvantage; that it is plastic. On the other hand; plastic covered with turf will have a very, very long lifespan." Ulf recommends contacting the Findhorn Foundation for more info in English since they've made several turf roofs in the past decade. He then cautions, "take turf from the ground, don't use soil and seeds as they did. The slope of the roof favours erosion - and you may end up lifting the soil up again and again."
Paul Miller of Hannibal, Missouri gave us a variety of ideas, including the innovative re-use winner: compact disks. Does anyone know how they might hold up? Overall, though, Paul made a strong case for tin roofs being the best solution for cost, protection, durability and re-usability, and ease of installation. So far, that's exactly the kind of roofs we've used on all of our buildings.
Frank Humiston gave another take on tin roofing and suggested making shingles out of flattened soda can ends. Jeff Martin suggested the same and making plastic shingles from 2-liter bottles as well. He also tells us that sharecroppers made shingles out of tin-can ends, though with no specifics on the overall effectiveness.
Benjamin Falk at the University of Vermont writes, "As far as shingles go you can make your own out of cedar or other rot resistant softwoods with a 'fro'. I thinkit is time consuming but that's how it all used to be done.... [It is] very sustainable: low embodied energy; nontoxic; renewable; etc...."Paul Miller also pointed out the possible fire hazard.
Only a few people even mentioned thatch, though it's certainly true that it's a very labor-intensive approach.
A few people mentioned tile, though only off-handedly. Some of us have considered this before, but the big question that remains is what to grout it with. Any ideas?
Finally, Melissa Wender referred us to www.crbt.org for all kinds of green building information.
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