In oups.com,
Todd typed:
5 years ago we had our original slate roof replaced on our
house built
in 1915 with 30 year Elk asphalt architectural shingles. The
roofers
did not have to replace any woof as it was all solid and in
good
shape. The wood beams on the roof are butted close to each
other with
little to no space between them.

Recently a large 6' x 4' section of shingles slide down the
south side
of the roof exposing the felt paper below. The original roofer
is long
gone. We called out another well known roofer in the area to
inspect/repair the section that fell.

His immediate reaction was that the roof wasn't nailed
correctly. He
threw down a section of shingles and showed us how the nail
heads had
pulled right through the shingles. He explained that there is a
nail
strip where you are supposed to nail into the shingle. These
were
nailed several inches above the area where he said was the
proper
place.

Only the south side has been effected so far and to be safe and
sure
we are going to have the entire roof replaced again.

The question I have is about the underlying wood and kind of
shingles
we can use. The roofer who came out and told us about the nail
strip
suggested that if we want to use an architectural shingle again
that
we re-sheet the entire roof with new wood. He says that the
nail
strip on an architectural shingle is too narrow and would need
new
wood. The nail area on a 3-tab is much larger and would not
require
new wood to nail on.

Another roofer says that's BS and if he did encounter any spots
that
were questionable, he would only re-sheet that area. The
difference is
about $2000 to have it re-sheeted or not.

Any other opinions? We'd really like to keep the architectural
shingle
look but are not sure whether or not we need to re-sheet the
entire
roof as the first roofer suggested. As I said above the wood is
in
good shape and there are no soft spots anywhere.

Todd

I'd go with the guy that only replaces what's bad. It makes his
estimate less accurate, but it makes more sense and is how we did
it. Roof's now about ten, and in perfect shape.
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