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: Installation

metal underlayment on ashpalt shingles

Return to Installation

Return to Forum

I have an old house with ashphalt shingles. A contractor recommended "white metal roofing" directly over the shingles. I understand there should be an underlayment of some kind. Are underlayment always necessary? What underlayments are suitable?
Ray Pethtel

12/10/2011
Share
Or copy this URL: https://www.metalroofing.com/spirit/comment/16892/find/
You will want to inquire both with the roofing manufacturer and check local building codes for the answer to this question, However, in most cases a layer of 30 pound felt, perhaps combined with a slip sheet OR simply a layer of a new synthetic underlayment will suffice. Also, ice and watershield is likely required on the roof perimeter and valleys in your area, per building code. Todd Miller
Todd Miller
Isaiah Industries, Inc.

12/10/2011
Share
Or copy this URL: https://www.metalroofing.com/spirit/comment/16893/find/
Is your current roof leaking? Did the contractor indicate why he wants to go overtop of the existing roof? While it is permissible, I always think that the investment in a metal roof deserves looking carefully at the roof deck. Most manufacturers will require some sort of slip layer if you are going directly over top. If you are going on battens you can usually do without. Check with the metal manufacturer for their specific guidelines and code as Todd mentioned. Eric Novotny
Eric Novotny
An informed customer is the Best Customer!

12/12/2011
Share
Or copy this URL: https://www.metalroofing.com/spirit/comment/16894/find/

If you would like to reply to this thread, please log in. If you do not have an Ask the Experts forum user account, create one here.

  • 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