I recently encountered an insurance company that would not insure a home
with a composition roof over a cedar shake roof. The required that all
roofing be removed first, new particle board or plywood installed and
then the new roofing placed on.

RB

houseslave wrote:
When you walk around the roof are there any spongy areas? If so then you
probably want to rip out the old and install new. Just make sure they
replace any damaged areas. If the roof is relatively flat with no leaks or
spongy areas then simply re-roof over the existing roof. I had my roof done
about 9 years ago and it is doing great. It was a second layer.