Primed and ready

By Emma Peterson.

Learn about why primers are so important for coating system success and how to pick the right one for your project.  

Recently, Megan Ellsworth sat down with Chris Underwood and James Atkins for an episode of CoatingsCast® to discuss primers and how to find the right one for your project. Chris is the product manager for roof coatings at Sherwin Williams, directly working with two brands, UNIFLEX and Kool Seal. James is the assistant product manager at KST Roofing and has been working with Chris for the last five or six years. Chris gave a look at the background of the role of primer in different coatings systems. He shared, “Primers are generally formulated to enhance adhesion and to seal the roof.” In general, there are four different types of primers — metal, concrete, single-ply and asphalt. When it comes to picking the right one for your project, James explained, “You would start by inspecting the roof to see what sort of condition it is and what substrates are already on the roof. It could even be multiple substrates.”  

Inspections are important because the condition of the existing surface can change the needs of the primer. For example, if you are working with an asphaltic surface, you want to ensure that the primer you choose not only seals and enhances adhesion but also prevents bleed through. If you are unsure exactly what you are working with, it is a good idea to do a pull test to make sure it will grab properly and the adhesion to the surface is good.  

Once you have determined what primer adheres properly and has the right performance for the substrate you are working with, it’s time to think about application. At its core, primers are applied much like any other coating. The main thing to make sure you get right when working with primers is the timing. Chris explained, “Typically a roofer may take a day to apply a primer, then allow it to get to a certain point of curing so that you can provide another, uh, coating over top of it and so that you get the proper inter coat adhesion between the two.” By making sure it has the time to cure, you give the primer the best chance to maximize the roof’s lifetime performance and avoid call backs.  

Read the transcript, Listen to the full episode or Watch the recording to learn more about picking the right primer!