end of quoted material
If all the airtightness is dependent on the integrity of a poly air/vapor
retarder, then your friend is likely to be correct. If the air barrier is
formed by successive layers of drywall, poly (probably not necessary!), dense
pack cellulose or low density foam like Icynene or Demilec, rigid sheathing,
then it is likely to be more robust. The key thing is to seal the big holes,
most of which are in the ceiling - chimney chase, duct chases, attic hatchway,
plumbing and electrical penetrations, etc. These seals should hold up over
time.
And I take your comment to support my contention of the dynamic wall approach
as possibly being too fussy in practice. Certainly, just a exterior door that
warps and no longer seals could probably account for half the incoming air,
replacing the air that would have been coming in the dynamic wall.
Marc
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