Lisa, Yes, thanks for reminding me about the Conservancy's application on Ellis. That is a good, quick and cost efficient method over worn out sheet metal, even gutters with conspicuous holes. I did another application, over 20 years ago, on a copper roof where every directly appliied elastomeric failed (turned to jelly or silly-putty) because of chemical reaction to prior patching compounds (black bitumin/asphaltic) The solution was to apply a barrier coat of fiberous neoprene before the elastomeric. It extended the life of the roof until replacement just recently...the elastomeric was even colored green to look like aged copper. I'm still concerned with bridging any moving parts with membranes thin enough to telegraph the historic roof pattern. I suspect the application Ellen refers to is a cost saving alternative to new metalwork without glopping up and grossing the building out. Thanks...Jim