Installation of metal roofing over shingles.
Underlayment for metal roofing over shingles.
The first one being that the new.
The quality and type of underlayments used on the project in the long term will affect the overall performance of the roof.
By removing the old roof before the new roof s installation you are able to give the underlayment a thorough inspection to ensure there are no damages that could.
If you choose to install metal roofing over shingles there are certain things you must keep in mind.
Our metal roofing profiles.
However contractors now recognize the benefits of synthetic.
The industry standard for underlayment is often thought of as felt paper tar paper but there are also many newer synthetic underlayments that are designed.
The first way is to run new underlayment over the existing shingle roof completely covering the old roof.
We re going to break them down so you know what to look out for.
If your metal roof is to be installed over solid decking or over existing shingles an environmental benefit a layer of quality underlayment between the two is essential.
And keeps the rough surface of the shingles off the backside of the metal roofing.
The first goal of roofing underlayment is to keep the roof deck dry before installation of the metal roofing material.
Install underlayment between the shingles and the new metal roof.
Underlayment is also a good idea when the roof is installed over battens though a natural tendency for the underlayment to drop between the battens can be a problem.
The main benefit of doing it this way is that it is the fastest way to install a new metal roof over a shingle roof.
This provides a couple of benefits.
So when we talk about metal roofing over shingles how does it work.
This can be synthetic underlayment preferred 30lb felt or a double bubble radiant barrier.
Installing a metal roof over shingles can also result in an increased chance of trapped water vapor and moisture between the new roof and old roof resulting in new mold and rot.
There are really two ways to install a metal roof over a shingle roof.
Underlayment must also act as a secondary weather barrier in case the roof fails.
2 install underlayment right over the shingles before installing the metal roof the second way to install a metal roof over a shingle roof is by applying an approved underlayment right over the old shingle roof.
A layer of underlayment installed on top of the existing shingles will help keep the granules of the old shingles from rubbing against the back of the metal and causing possible corrosion.
But first here are a few precautions about the underlying material.