While there are many threads and posts relating to coating roofs, I did not find any information about why to or not to use certain types of elastomeric coatings. Skip to the HENRY section if you want the summary.
Things I think we disagree on:
Roof coatings.
Things I think we can agree on:
White reflects heat, thereby it keeps the inside of the vehicle cooler.
Roof coatings are more effective than plain paint in cutting internal temperatures. Read this thread:
http://www.skoolie.net/forums/f13/in...se-9291-4.html - Jazty's test starts around Page 4 - post 38.
Roof coatings (paint or otherwise) do help seal a roof, but they are not meant to fix leaks.
Yet, if you do want to apply a roof coating, here's what the tech support at Henry coatings said about their product.
HENRY Tech Support:
They recommend the Tropicool 887 Silicone versus their Acrylic based product (or any silicone product versus any acrylic based product) because:
Acrylic is not compatible with:
Fiberglass roofs
EDPM covered roofs
Aluminum roof coatings
Acrylic does
not have the material elongation needed to resist constant small torque movement of the vehicle, tends to start to detach over time at speeds of around 35+mph and when it starts breaking down and forms cracks, then water seeps in causing it to detach, bubble and cause water issues.
Silicone will adhere to Fiberglass, EPDM and aluminum roof coatings and is the only product Henry will guarantee on RV type vehicles.
Per the issue that "nothing" will stick to the silicone roof coating, this is the inherent nature of the product. But, that doesn't mean if you need to attach something to the roof you can't scrape away the silicone coating, attach whatever and then recoat with the silicone product.
Hope this helps others.