[nota]

lots of foam roof problems years ago here in s fla
no idea if it is the same as SPF or even is a BASF product
but think the newer codes banned it here

are you in a fire danger area ?
or wild weather ?

I am amazed at pre-dark age teck in roofing
the best we have is tar paper over wood with tile on top
romans did that 2000+ years ago

bahama style 3 layers of a/c plywood screwed and glued
like a boat hull is the best for hi winds
most just paint the wood with quality paint
but s fla codes willNOT allow that
you can nail gun up one layer of cdx but then have to use tar paper
and a code nail count and the shingles or tile with more nails
and the result a good class 4 or 5 cain will blow the whole thing off
while the bahama screwed and glued painted roof stays in place