[Greenbuilding] And the debate rages on to add an air barrier or not to air barrier!

[George J. Nesbitt]

Joshua Lloyd wrote:
> Brick Veneer
> 1" air space
> 1" Foil faced Polyisocyanurate
> 1/2" Exterior Gypsum Board
> 6" Metal stud w/ Unfaced Fiberglass batts
> 5/8" Gypsum Board
> Latex Paint
My thoughts would be this:

     Brick Veneer with stainless steel ties
     1" air space
     4" Foil faced Polyisocyanurate, taped seams
     Tyvek Stuccowrap, tape or caulk all seams especially at top and
bottom of walls, because it is not an air barrier unless fully sealed
(studies have show houses are no tighter with wraps because there not
fully sealed. Just never follow their advice and us only one layer under
stucco! This will act as you air barrier, and weather barrier if any
water gets through the 1' air space/ drainage plane, or if you get
condensation on inside of foam.
     1/2" Exterior Gypsum board
     6" metal suds with no insulation, fiberglass batts or spray foam.
the steel studs conduct heat so well that it doesn't matter as much what
you insulate with because the whole wall R-value is so degraded. This
will also allow the stud space to dry out if or when it gets wet.
     5/8" Gypsum Board
     No VOC paint