The underlayment of a metal roofing system is not visible. However, it does help to protect the home from water damage. When a metal roofing system is installed on a home, typically, two underlayments are used. If moisture needs to be prevented from damaging the attic or deck, whether there is metal shingle metal roofing or a standing seam system, it's important to have the right underlayment.
With an underlayment, the deck has more water protection, and a "slip sheet" is also provided where the metal can move on the roof deck due to contraction and expansion. When the proper underlayment is installed correctly, a home may be kept safe and dry for a lifetime.
Different Kinds of Underlayments
When installing a metal roof, it’s important to consider the best type of underlayment that can be used. Not every type of underlayment is a good fit for every home. There are three main types of underlayments we will take a look at: synthetic underlayments, ruberized asphalt, and nylon mesh.
High tech performance is provided by multi-layer construction along with polypropylene. You will see a stronger tear resistance with those that have scrim reinforcement. They also need to have a safe, non-skid surface that the crew can walk on.
You will see the combined benefits of asphalt-saturated underlayments and non-bitumen with ruberized asphalt. It's also fully waterproof because it has a higher asphalt and also rubber polymer content. This type of underlayment is most suitable for metal roofing installations.
These underlayments are typically used when a hot roof system is being utilized along with closed cell foam insulation.
When installing a metal roof, it's important to consider which type of underlayment is going to be the best fit. Just remember to evaluate each project individually to determine the best type of underlayment.