Troubleshooting Roof Membrane Coating Not Allowing Seam Tape And Sealants To Stick

Updated 06/27/2023 | Published 06/26/2023

Question:

Recently purchased a 2000 Shasta 5th wheel. I noticed the previous owner had at one time began to coat the roof but left a third of it unfinished. So we decided to give it all a new coat. We scubbed with powder detergent and water . A friend gave us some eternal tape and Dicor lap sealant to do our roof seams first. To our suprise neither would adhere to whatever top coating the previous owner used. We even used acetone sparingly with no luck. From what I seem to read on line, This suggests the previous coating what a silicone coating? The area not coated both the lap sealant and tape stick. To make sure the new coating adheres properly to the previous coating, what products would you suggest.

asked by: Bob D

Expert Reply:

Without knowing what the coating is made of there's no way to confirm what would actually stick to it. We currently only offer the Alpha Systems 4034 Roof Coating for RV Roofs # AL34CV, which is ok for use on polyurethane foam, aluminum, galvanized steel, fiberglass, cured concrete and EPDM roof membranes. When I reached out to Alpha to see if they had heard about anything like this they stated you'd most likely have to remove and replace the membrane. If you can still contact the person you purchased the trailer from I would reach out and see what he used and then we can look for solutions.

expert reply by: Kevin C