Insulation no decking

I have a 30 year old house with a metal roof. There is no plywood decking. There is insulation on the floor of the attic, but not on the metal roofing itself. Is this correct, or can I insulate the underside of the metal itself? I can't tell if there was insulation next to the metal originally and has fallen away over the years due to some water leaks and repairs. Please advise.		Janet Field 6/5/2014	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/19548/find/
You could insulate this and, if you do, I would suggest a closed cell spray urethane foam system. Other insulations, especially if not done with a solid vapor barrier, could trap moisture against the bottom side of the roofing which would be harmful. I will say this though ... my suggestion for your climate is to ventilate the attic as much as you can and then add insulation on top of your ceilings rather than beneath the roof.		Todd Miller Isaiah Industries, Inc. 6/5/2014	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/19549/find/
Janet, If the roof is currently vented (i.e. the attic is not a conditioned space nor used as one), don't bother. Leave it as is and use a proper roof with the right emissivity for your area and climate. Make sure the insulation is up to R-50 and air seal the attic floor.		Eric Novotny An informed customer is the Best Customer! 6/6/2014	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/19550/find/

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