The first one being that the new underlayment will act as a second line of defense in case water would to somehow get underneath the metal roof.
Metal roofing directly over shingles.
By placing metal roofing over shingles you can save in the labor costs of ripping them off while also preventing them from being thrown into landfills.
Can you put metal roof over shingles.
But some steel shingle manufacturers offer do it yourself systems that cost about the same as an installed asphalt roof.
If you don t want to take our word for it check with your local building department.
Can you put metal roof over shingles.
Metal roofing weighs less than one pound per square foot.
Disadvantages of metal roofs.
These systems aren t attached to a frame but instead install directly on the old roof.
Our metal roofing profiles.
Metal roofs over shingles will also provide an extra layer covering your home helping to further insulate it.
Second the frame creates a flat and straight surface even when the shingles are badly curled or the roof ridge is bowed.
The low weight of metal roofing is one thing that encourages this.
Installing the metal roofing over 1x4 s allows the ability to also install additional insulation under the metal roof.
There are really two ways to install a metal roof over a shingle roof.
Consequently they don t have the same ventilation advantages.
Asphalt shingles can weigh up to four pounds per square foot depending on the brand.
This provides a couple of benefits.
The first way is to run new underlayment over the existing shingle roof completely covering the old roof.
Metal is the best choice due to its very low weight per square foot and its unique design.
First because the frame is screwed directly to the rafters and the interlocked shingles are screwed to the frame the roof can withstand winds of up to 120 mph without damage.
So when we talk about metal roofing over shingles how does it work.
Advantages of metal roofs over shingles.