RE: [GBlist] Qustn: Rigid Insul above exist'g roof

[Scott Schreffler <ScottS@bumgardnerseattle.com>]

I don't think you need to vent.  A rule of thumb is to ventilate when the
insulation is on the inside.  No vent if insulation on the outside.  That's
why you don't have to vent when you use a SIP.  Essentially it's on the
outside.  If you do the "green" thing here, and stack ventilation on the
existing roof (no waste to landfill) then it's adding insulation onto the
outside.  

No ventilation needed.

Scott Schreffler
Seattle

<<so the qwuestion is...to vent or not to vent>>

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