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: Roofing over existing roof

Vertical Metal roof over Cedar shakes on A Frame

Return to Roofing over existing roof

Return to Archive

Return to Forum

This topic has been closed by the administrator. Comments are no longer accepted.
We have just purchased an A Frame (no attic) lake cabin in Iowa. It currently has cedar shakes that are about 25 years old and covered with moss and possibly mildew. The area is wooded and mostly shaded. It has been suggested that we can put a vertical metal roof over the shakes, with horizonal 2x4 stripping to screw it into. They have also suggested 1.5 dense foam insulation between the stripping for additional insulation. Our question is if the moss and mildew will be a problem underneath the new metal roof, or any other potential issues. We would prefer not to remove the roof if possible. Thank you for your advise. Gordon
Guest User

12/27/2003
Share
Or copy this URL: https://www.metalroofing.com/spirit/comment/2547/find/
Chances are that the a-frame construction has little or probably no ventilation. The cedar shakes, by their nature, have breathed a fair amount. Unless there is a strong vapor barrier in place on the inside of the roof someplace, I am concerned that moisture and condensation problems will result. Also, if just horizontal lathes are in place, you will end up with a very uneven surface. If the shakes are left in place, there are some metal shake and tile profiles designed for application over shakes. Another option is to use vertical lathe over the shakes, followed by horizontal lathe or decking, creating an eave to ridge vented airspace. I strongly suggest using this website to locate some manufacturers of quality metal roofing in style you like and then contacting those manufacturers to work out details of how they feel their roof should be installed on your home. All I can give you is here is generalities. You need to speak more in depth with the manufacturers of the products you might specify.
Guest User

12/28/2003
Share
Or copy this URL: https://www.metalroofing.com/spirit/comment/2548/find/
  • About the MRA
    • Member Companies
    • Leadership
    • MRA News
  • For Professionals
    • Join the MRA
    • Industry Resources
    • Upcoming Events
  • Contact
  • Subscribe
©2018 Metal Roofing Alliance. All Rights Reserved. Privacy Policy Terms and Conditions