It's time to get the roof redone, which isn't too big of a problem. The
roof is very simple (a basic gable and 2 separated, smaller hips) and
I'd consider doing much of it myself if it was a more comfortable pitch.

Anyway, I did have one question. The roof is old (1915) and originally
was the shake shingles on 1x6 planks. The shakes are no longer there,
but the planks remain and are now covered in 4-5 layers of asphalt
shingles. My plan is to have the contractor strip down to the planks
(which will make a huge mess in the attic unfortunately) and cover them
with 3/8 or 1/2 CDX. The only real problem I see is the planks on the
overhangs (about 18") of the gable ends droop noticeably so I'm
concerned with how the CDX should be attached on the edges. I fear
staples or nails would eventually pull away so I was considering
requiring them to screw the end pieces.

What do you think? The best way would be to just replace all those
boards, but that will involve more work, and we need to keep this
inexpensive.

My other concern is the chimney, which has deteriorated quite a bit over
the years (we've been here only 10 years). It appears a few decades ago
somebody put a coat of mortar over the whole exterior and painted it
with a silver colored substance. That has since cracked and pieces have
chipped off over the years (I've found several chunks in the yard while
mowing). 3 years ago we had a new furnace put in that required a sleeve
and they installed a galvanized sheet metal cap over the chimney, which
comes down the sides about 4-6". It has never leaked since we've been
here (that I'm aware of).

My thinking is I need to have the chimney fixed up prior to the roof
being done so no damage is done to the new roof. I was thinking maybe I
could get by with either having it rebuilt from roof level up or
preferably to just remove the chimney so only the sleeve comes out of
the roof (it's just furnace/water heater, no fireplace)? I assume that
is all they do when a new gas furnace is installed when no chimney
exists. Is that practical?

Thanks,
Michael