Primers and Mod Bit / Asphalt Roofing / Gravel BUR
This week, we’ll be looking at modified bitumen and aged asphalt roofing systems. For these substrates, primer is not necessary. The silicone will hold and maintain a strong bond, but we have actually developed a primer just for these roof types. Why you ask? Because a white roof doesn’t remain white for too long without it.
With modified bitumen and asphalt roofs, silicone can begin to yellow pretty quickly after the silicone is applied. This yellowing is due to activating asphalt bleed through from the asphalt and bitumen. Although this bleed through does not negatively affect the silicone’s integrity, it can be unsightly if you were hoping for a dazzling white roof.
To help prevent this yellowing, we offer P-160 Bleed Block Primer. This primer has been designed specifically to stop this bleed through, offering you protection of your beautiful, white rooftop. If you or your client don’t aren’t concerned with roof color, you can skip this step altogether. The watertight roof will still last decades. If, however, your roof is a point of pride, this primer is a must-use on these substrates.
Please check in next week as we look into the trickiest substrate of all – EPDM. If you’ve ever coated over EPDM before you probably already know how stubborn this substrate can be. If not, make sure to follow along as we look into what it will take to get great adhesion on a complicated roof!