On Fri, 10 Jul 2020 05:03:48 -0700 (PDT),
wrote:

Liquid EPDM Rubber is not advised for asphalt shingles, stainless steel or glass. The following roof types-substrates do not require the ProFlex primer and only one coat of the Liquid EPDM:https://www.epdmcoatings.com/epdm-uses.php


There was a product called "roof-saver" if I remember correctly that
was sold for use on all kinds of roofs - including steel and asphalt
shingles. An uncle of mine was selling it in Sask. a number of years
back. No idea how it worked or if it was any good. He has since passed
on.