Volume 2, Issue 10 (November 2005) A Review of Climate Loads
Relevant to Assessing the Watertightness Performance of Walls,
Windows, and Wall-Window Interfaces When assessing a wall
assembly's ability to manage rainwater and control rain
penetration, the two key climatic elements to consider are wind
speed and rainfall intensity. However, of significance to rain
penetration is the effect of wind-driven rain on the building
cladding — that is wind coincident with rainfall. When water is
present at openings in the cladding, water is driven into the
layers of the assembly by the action of wind. Paths providing a
direct line from openings in the cladding to inside the assembly
offer particularly vulnerable points for water entry.
Performance testing helps determine the location of vulnerable
locations in a wall assembly and the test loads at which
penetration occurs, and it possibly relates the amount of entry
to specific details and simulated climate effects. Undertaking
watertightness performance tests requires