Join the MRA | Member Login
Find a Professional
  • Why Metal Roofing?
    • About MRA
    • Benefits of Metal Roofing
    • Compare Roofing Materials
    • Homeowner Testimonials
    • Inspiring Metal Roofing Projects
  • Homeowner Resources
    • Metal Roofing Buyers Guide
    • Resilient Housing Guide
    • Metal Roof Sustainability Guide
    • Above All Else You Need a New Roof eBook
    • MRA News
    • Member Provided Resources
    • 3rd Party Articles
    • Frequently Asked Questions
    • Preparing for Hurricane Season
  • Gallery
  • Visualizer
  • Ask The Experts
    • Energy Efficiency
    • Existing Metal Roof Questions
    • Installation
    • Is A Metal Roof Right For My House
    • Metal Roofing Benefits
    • Product Selection
    • Other
    • Archive
  • Find a Professional
Join the MRA Member Login
Sign Up Log In Add New Topic

TOPIC: Condensation Issues

moisture barrier under tin?

Return to Condensation Issues

Return to Archive

Return to Forum

This topic has been closed by the administrator. Comments are no longer accepted.
i am in middle of building an addition (lean-to) on old house, basically extending roofline over to bedrock. For slope reasons(mountain) and snow load, the roof/ceiling are one section, 4" thick, heavily braced every 2nd truss. I had to sheet and poly the roof because of weather, it is raining for days. I have tin for the roof. Now that I go to finish with insulation and vapour barrier on ceiling; do I need to remove the poly that was placed on roof over sheeting? Can I put tar paper over this poly and install tin? Will there be a moisture loss between the poly and the sheeting? Or should the tin go straight on the tar paper? I am venting on the low end of roof in-between each section. I have been told that there will be moisture loss that will ruin the roof sheeting. thanks
Guest User

10/16/2009
Share
Or copy this URL: https://www.metalroofing.com/spirit/comment/14032/find/
"Moisture loss" ... not sure I understand that. As long as you have excellent ventilation in the attic (intake and exhaust) you should be okay with the non breathable underlayment. Todd Miller
Todd Miller
Isaiah Industries, Inc.

10/25/2009
Share
Or copy this URL: https://www.metalroofing.com/spirit/comment/14033/find/
  • About the MRA
    • Member Companies
    • Leadership
    • MRA News
  • For Professionals
    • Join the MRA
    • Industry Resources
    • Upcoming Events
  • Contact
  • Subscribe
©2023 Metal Roofing Alliance. All Rights Reserved. Privacy Policy Terms and Conditions