How much trouble with the wrong underlayment?

I am going to get a metal roofing on top of a new 12" thick SIP roof. The SIP installer put Owens Corning Weatherlock Mat & Owens Corning ProArmor on the roof to prep if for my metal roof. The first roofing quote I received recommended removing those underlayments because they were not appropriate for metal roofing. I called Owen Corning and they recommended removing those and installing Owens Corning Weatherlock High Temp Metal and Tile and Owens Corning Deck Defence. The SIP installer insists that it is fine the way it I would like to get a better understanding from the metal roofing point of view. Should I remove what is there and what bad things will happen if I don't? Respectfully, Dave		Guest User 4/26/2016	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/21166/find/
What color is the roof? What type of metal roof is going down?		Eric Novotny An informed customer is the Best Customer! 4/26/2016	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/21167/find/
You may think this is a cop-out but, in all frankness, the opinions that matter here are the metal roofing MANUFACTURER and the underlayment MANUFACTURER. If something goes wrong, they will be the ones you will later look to for help. You want to make certain that the installation was in keeping with the specifications if that situation should ever arise. Now, as far as my opinion, I think you're okay as planned. Again, though, and I can't stress this enough (sorry for SHOUTING earlier) -- my opinion means nothing should a problem arise.		Todd Miller Isaiah Industries, Inc. 4/26/2016	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/21168/find/

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