Practical Tips for Installing Underlayments in Cool Weather

Practical Tips for Installing Underlayments in Cool Weather

  Cool weather underlayment installations can be made easier by following these simple guidelines.

Cool weather underlayment installations can be made easier by following these simple guidelines.

MFM Building Products produces a number of self-adhering, or self-stick, underlayments that typically have a minimum installation temperature. In general, MFM recommends installing its roofing underlayments in fair weather at temperatures at 50°F (10°C). Warmer temperatures enhance the adhesion properties of the rubberized asphalt membrane, reducing the chance of encountering problems during installation.

Should the underlayment need to be installed in temperatures below 50°F (10°C), the following recommendations should be considered:

  • Always follow the product's installation instructions carefully
  • Make sure there is no moisture present on the substrate - moisture, dew or frost will prevent the product from fully adhering to the substrate
  • Prepare all masonry, bare metal, and aged or damaged wood surfaces with an asphalt-based primer - allow primer to completely dry before applying product
  • Keep the underlayment in a heated area such as a building, vehicle or hot box with a temperature of 60°F (15°C) or greater
  • An electric air gun or hair dryer may be used to gently warm the membrane and substrate
  • Always roll the entire surface, paying special attention to any overlap area, for full contact with the substrate
  • MFM Spray Ahesive™ can be used as needed in cool weather installations

If you questions concerning the installation of MFM Building Product underlayments, please contact MFM Technical Services by calling 800-882-7663.