[SustainableTompkins] sustainable roofs for houses (so far as is possible)

[Simon St.Laurent]

I've been repairing my old house for a few years now, and I've been
postponing replacing the roof.  It's time to stop doing that, and I now
plan to replace it next year.

What are the options for a roof that will last as long as possible with
minimum negative impact on the environment and minimum need for
maintenance?

Most of what I can find online about sustainable roofs is for commercial
buildings, and I suspect climate matters a lot for this, so I'd be
especially interested in local input.

As you can see at:
http://livingindryden.org/images/home/completedFront06242005A.jpg

The roof is fairly steep and has a few extra things popping out of it.
The back is a simple slope.  It needs to be a complete tear off.  The
bottom layer is cedar shingles, and the top two layers are asphalt.

A green roof (with plants growing on it) won't work on that slope, and
solar panel roofing tiles are also unlikely to generate much power
because of surrounding trees.  

I'd really prefer not to go with metal, both for aesthetic and for
long-term maintenance reasons, but could consider it, and certainly
would be interested in hearing what options there are.

I don't think the house was built to support a slate roof.  It probably
could, with all the old barn lumber used, but somehow that feels like
overkill.  Though maybe there's local slate?

Cedar shingles are intriguing, though I've heard they have dire impacts
on home insurance rates, and I'm not sure how genuinely sustainable they
are anyway. (I've heard awful things about cedar mulch, though I don't
know how comparable that is to shingles.)

It may well be that asphalt or recycled plastic are the best options - I
just can't find much that gives me a detailed comparison.

I know roof-buying is an occasional thing, and new would probably be
different from renovation, but I'd be very interested to hear from
people who have ideas for minimizing the negative impacts of this
one-time project on the world.

(I'm planning to do some other improvements along with the roof.  First,
gutters that flow into water catchment for the garden.  Second,
eventually a solar water heater and possibly a small solar installation
on the back of the house.)

Thanks,
Simon St.Laurent
http://livingindryden.org/