Is replacement of decking when removing old shingles required?

Guest User
7/14/2007
My single story ranch has a 2 layer, 4 pitch hip roof of about 30 squares with 1/2 inch plywood decking and two chimneys (don't know if all this info is relevant...). I intend to have the existing asphalt shingles removed before having the metal roof installed. One contractor told me that he would have to replace all of the decking if the shingles are removed. Is this true? No other contractor has mentioned this and right now I only intend to have the damaged decking replaced. Also, do I need an ice barrier around the perimeter of the roof as with asphalt roofs or is new underlayment sufficient? Thank you.
Ken Buchinger
NCI Building Systems, Inc.
7/16/2007
You would only need to replace damaged decking. I like to use a peel and stick memebrane around chimneys, valleys and any other areas that tend to be tricky or channel water from the roof. If the potential for ice dams exists, depending upon the roof panel type, I might also use it along the eaves. Ice dams typically form when you have heat loss through the attic, which melts ice and snow on those marginally freezing days. At the eave, where there is no heat loss, the water can refreeze, creating an ice dam. If the panel is a snap together type, I would want to use the peel and stick memebrane. If the panel is a field seamed type and has no breaks near the eave (i.e. a porch roof at a different roof slope)then I would be conmfortable without the peel and stick memebrane at the eave.
Find a Contractor

Get Started Today

Take the first step to increasing the value of your home with a great looking, durable, fire resistant and energy efficient metal roof. Browse our list of qualified MRA Member Roofing Contractors in your area for a free consultation and estimate.