To Prime or Not to Prime...That is the Question — MFM Building Products Corp.

To Prime or Not to Prime...That is the Question

To Prime or Not to Prime...That is the Question

This parapet wall and low slope surface has been primed with an asphalt-based primer prior to the application of Peel & Seal®.

This parapet wall and low slope surface has been primed with an asphalt-based primer prior to the application of Peel & Seal®.

The headline says it all. And builders, whether the more experienced contractor, manufacturer, or dealer, should be asking this question. Priming the surface can be a critical step.

For this continued dialogue on MFM Building Products’ roster, we’ll discuss Peel & Seal®. This benchmark product is the original, self-stick roll roofing specifically designed for low-slope residential and commercial applications. Peel & Seal®’s patented formula (consisting of laminated aluminized foil, high-density polymer films and a thick layer of rubberized asphalt) provides a durable and maintenance-free roofing surface.

In this photo, Peel & Seal is being installed directly to the primed surface. No need for any special glues, coatings, hot torches, etc.

In this photo, Peel & Seal is being installed directly to the primed surface. No need for any special glues, coatings, hot torches, etc.

However, some substrates require an asphalt-based primer prior to the application of the product — very important for the best possible adhesion. In fact, the better the contact with the substrate, the better that Peel & Seal® will perform. In some cases, a surface does not require priming and the product can be adhered directly, but any surface containing dust, debris or dirt will compromise the bond. 

Here is the finished product. Peel & Seal® is designed to be permanently exposed to the elements and carries a 10-year limited warranty.

Here is the finished product. Peel & Seal® is designed to be permanently exposed to the elements and carries a 10-year limited warranty.

MFM Building Products gets a lot of technical calls with questions about applying Peel & Seal® to various surfaces, so below are some common construction surfaces and suggested preparations. In the end, though, the key to correct installation is a clean, dry, and flat surface.

COMMON CONSTRUCTION SURFACES:

  • Wood (weathered wood must be primed)
  • Metal (rusty metal must be primed)
  • Plywood (weathered plywood must be primed)
  • OSB (weathered OSB must be primed)
  • Composition Board (must be primed)
  • Fully Cured Masonry (must be primed)
  • Rigid Insulation Board
  • Smooth Asphalt Roofs
  • Fiberglass Base Sheets (must be primed)
  • EPDM Roofs (must be primed with an MFM-approved EPDM primer)
  • Mobile Homes, Campers, RV Roofs

Please let us know if there are any surfaces that you have had problems with or you can contact MFM Technical Services at 800-882-7663.