Why not integrate window exterior into WRB?
I've recently noticed that several folks are not advocating flashing the exterior side of windows (flanged or unflanged) into the water-resistive barrier (WRB), but instead propose that a properly flashed rough opening (RO) and an airtight interior is sufficient to manage water drainage and air sealing. Notwithstanding window manufacturer recommendations, would it not be prudent to flash the top and sides of the window to limit what water can make it into the RO in the first place? It's not much extra effort/expense. Jesse Thompson's recent article in FHB spoke of design pressure issues, which seem to be at play. Admittedly, I don't fully understand the role of DP. To confuse me further, 475 sells a tape expressly for this purpose (Contega Exo), claiming it to be a wind-weather barrier that works in conjunction with the interior air sealing tapes.
Would someone care to explain why, in light of DP or other reasons, it would be better not to flash the window exterior?
Thanks in advance.
Posted Sun, 02/03/2013 - 14:27
Edited Mon, 02/04/2013 - 07:07
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