Roofing underlayment
Emel
| Posted in General Questions on
Our builder is building our home with a vented attic and zip sheathing for the roof. The roofer had planned to install a roofing felt under the metal roof. For condensation and to avoid moisture issues, we have asked him to use an impermeable membrane first over the entire roof. He said he could do this. Would any brand roof or ice shield over the entire roof work here or is there a certain impermeable membrane that works best? Also, this would negate the need for felt, correct?
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Replies
Use an underlayment approved by the metal roof manufacturer. They often publish this on their websites
Emil,
Synthetic underlayments work well. You don't need I&WS over the whole surface.
As Bill said, the underlayment needs to be rated for metal roofs so it can withstand the heat generated. That’s why roofing paper is a poor choice. It gets so hot it adheres to the panels, and then tears as they move.