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TOPIC: Other

Ventilation under the metal oanels

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What is the required minimum air gap for above sheathing application?
To get more ventilation under the panels would a dimpled mat or entangled mesh suffice?
Panels are going to be striated--would you recommend more ribs on the panel for better insulation?
The air flow is just from the panel eave entry and exits at the top ridge vent which is just for the panels since the interior attic will be conditioned with closed cell foam under the plywood -so the ridge vent is only for the hot air from the panels.
lc010457
Metal roof ventilation

11/4/2021

I do not know that there is a required minimum air gap per se. However, you can move as much air (NFA) as your ridge vent allows, provided your air path allows it. Most ridge vents may allow something like 18 square inches per running foot, drawing from both sides. An entangled mesh would probably be closer to 6. However, you're not trying to circulate air through a volume of space like an attic. And part of the value of an entangled mesh is the thermal break. Many people use it without trying to actually move air through it. I feel like an entangled mesh or similar will do fine. The other option would be cross battening.
Todd Miller
Isaiah Industries, Inc.

11/4/2021

Thank you! Would the entangled mesh be best in long vertical strips between the fastening clips under the panel so the clips are not going right on top of the mesh or totally horizontally across the deck and the fastening clips will go right on/over the mesh
lc010457
Metal roof ventilation

11/5/2021

The clips are best if seated over the mesh. Otherwise, they will pull too tightly against the panels.
Todd Miller
Isaiah Industries, Inc.

11/5/2021

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