[Cob] Alternative shingles

[Dognyard]

Thank you everyone for your ideas!!

I should have been clearer and asked for ideas in recycled materials
too. (I have this vision of a roof shingled entirely in used license
plates - wouldn't that be colorful??). And when I said "not concrete", I
mean not cement, but as soon as I sent the message I figured that a
home-made shingle of earthen materials would almost have to include
cement or lime as a component.

I could certainly see something like shotcrete working, as long as an
air space were left between it and the sheathing. If I'm thinking
correctly, cement can wick moisture quite easily if it's not
waterproofed with something black and smelly :-) - right? So an air
space might work to solve that, and could be easily achieved with
strapping. Not a treeless solution, but a solution. But I think I would
need to consult an engineer about roof loads before we could do that.

We live in an arch rib type building. Also called a "quonset". It's
basically all roof, and very steep at that, so re-roofing is a huge job
no matter how we look at it. It is currently roofed with cedar shingles,
and they are about at their age limit. I doubt it was all done very well
to begin with, as we have leaks now in almost every valley. We keep pots
in the living room in the summer. So we are looking at re-roofing in the
very near future. So far I have looked at a metal roof, but was very
curious about alternatives that might be less expensive, but otherwise
durable. I don't think we could ever sell the house if I shingled it
with license plates :-). Whatever we do has to pass code (even if I have
to beg and plead), and it has to look acceptable (not that the rest of
the house does).

For a couple of years now, I've been working on a site in the woods. An
injury prevented me from doing much on it last year, so it's still
pretty much just a hole in the ground. It will be cob, but will be a
whole lotta roof too. I was going to stick strictly with materials
available to early settlers in the area (poplar, cob, and marsh
grasses), but I've evolved past that now. It will be whatever I want it
to be, and made with whatever materials I can get my hands on. It may
have a living roof, and since I plan to spend no money, or very little
money at least, I will have to be extra creative with waterproofing it.
Or I may start collecting license plates :-). But it would be fun to use
the experiment to try a stabilized earthen roof, or making tiles. It
would look really neat with home-made tiles to look like slate. It would
mean I'd have to cast each one but I have no time limit.

Karen Clouston