Why NOT to apply Metal Roof Coatings - The worst thing to ever do
Channel: Flat Roof Doctor
Date: 17/11/2019

https://bergstromm.com/
Are Metal Roof Coatings Good or Bad? See the issues of acrylic coatings and how to repair a metal roof with Turbo Poly Seal.
See the Flat Roof Doctor's opinion on Astec Acrylic Coatings - https://www.icc-astec.com/resources/products/
https://bergstromm.com/ for Turbo Poly Seal
FTC Affiliate Disclaimer -  I get commissions for purchases made through links in this post.
The worst thing to ever do on a Metal Roof is to completely coat it. Any coating is like a paint that will bubble, peel, and crack, causing water between the coating and the metal.

Acrylic coatings are thick paints. It dries out and shrinks with the extreme heat from the sun, causing it to pull away from the corners of the metal panels, and then a crack sets in. Water enters this crack and follows the corner between the coating and the metal till it reaches a fastener or seam and causes rust or a leak.
https://bergstromm.com/product/turbo-poly-seal-roof-repair-kit-5-ft/

Summary:
1. Acrylic coatings are a type of water-based paint that shrinks and cracks
2. Metal roofs get extremely hot and cold, causing expansions and contractions
3. Fasteners constantly wear out and loosen up, causing the Acrylic paint to crack around it
4. The expansion and contractions of two overlapping panels are more than any acrylic coating can withstand without cracking
5. The surface of existing metal roofs is not clean enough to have paint sprayed, and therefore, the paint will not adhere properly
My best advice is to repair the seams, seal the fasteners, cover the rusty areas with Super Silicone Seal, and leave the rest of the metal surface bare.

Start:
0:00 - Coatings on a Metal Roof
0:18 - Shrinking Acrylic Coating 
0:55 - Water trapped under the coating
1:18 - Coating causes rust around screws
1:42 - Ice under the coating
1:54 - How to fix the problem 
2:05 - Using Flat bar 
2:15 - Using hammer claw
2:25 - Removing Hex screws
2:41 - Tip on Grinder use
3:00 - Using a grinder to remove the coating
3:20 -  Replace screws with Pan head screws 
4:15 - Turbo Poly Seal to seal
4:44 -  1st coat of Turbo Poly Seal
5:15 - Embedding Fleece
6:03 - Final coat Turbo Poly Seal
6:49 - My take on Metal Roof Coatings