In a message dated 2/21/2000 2:05:56 PM Eastern Standard Time,
[log in to unmask] writes:

<<  1) Extractives in some woods and waxes in hardboard
 siding will act as surfactants that make water penetration through the
 wraps very easy. 2) If the cladding or brick veneer are wet then heated
 with sun, the vapor pressure in the cavity will go high, so the vapor drive
 is strong toward the inside of the building. Both companies are doing
 product modifications. >>

Bill,

#1 I'll take your word for.

On #2, if you get all this water/moisture/vapor from the heated wet masonry,
isn't it (theoretically, at least) going to condense on the cold surface (the
housewrap), and dribble down the housewrap until it dribbles out the weeps
(assuming you had weeps to begin with, that they didn't get clogged, and that
the 10,000 holes you put in the Tyvek  to nail in brick ties didn't cause the
Tyvek to leak like a sieve anyway), rather than passing through the Tyvek?

Have the Fine Homebuilding guys (and guyettes) observed these conditions?