Found a piece of roofing shingle in a flower bed at the weekend. Not an
expert (yet) but it is probably the asphalt type. Got out the
binoculars--there are several places where a 3 to 4ft wide piece of shingle
is missing, essentially all of the shingle that sticks out from under the
shingle above it, but the edge of the remaining bit is ragged.

It looks like there are shingles of a different color underneath. There was
maybe 1/2" of granular material in some of the gutters when I cleaned out
the leaves last autumn.

House is about 30+ years old. Don't know how old the roof is since we've
only been here a year, but it's probably over 10 years old.

I'm guessing I may be looking at a new roof. Is it common practice to put
shingles over older shingles? How many layers can you go? Or does it make
more sense to remove existing shingles back to the wood?

Any thoughts welcomed. I won't be doing the work myself.

Greater Richmond, Virgina area.

Thanks, Sam