We plan on creating an unvented 1:12 pitch roof assembly with standing seam metal panels and closed cell spray foam on the interior. Does the roof decking/OSB need to have gaps in between each board for expansion/contraction on an unvented roof assembly? Also will Owens Corning Titanium PSU30 be an adequate underlayment for an unvented roof? (it is rated for 1:12 pitches under metal panels but not sure if it’s ok for unvented assembly).
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A collection of one thousand construction details organized by climate and house part