EPDM roof Lap sealant ?

[opfor2]

Hi there,

I am about to re-seal my EPDM roof on my 21' toy hauler and I noticed that the EPDM Lap Sealant around my vents is cracked and lose. My question is do I attempt to remove the old lap sealant or just apply new sealant atop of the old?

thank you,

Danny

[PSU Turf]

If you can peel off the old sealant I would definitely remove it. Leaving it in place, with its associated cracks and gaps, will decrease the effectiveness of the new sealant. I would avoid using any metal scrapers to remove the old stuff to avoid damaging the membrane. Be sure to use the recommended cleaner / solvent to prep the roof before applying new sealant.

[Too Tall]

There are some pretty good YouTube videos on this but in short, they tell you to clean it with mineral spirits and then apply self leveling Dicor. If the old one is cleaned well you can go over the top of it as long as it is still adhering to the surface rubber. As mentioned, if the old one can be peeled up easily then remove it and start from scratch.