Brick Veneer Weep-Hole Count (IRC R703.8.6)
Weep holes to drain the veneer air space at each through-wall flashing line: weeps per line = ceil(wall length in / max spacing) + 1, so both ends get a weep. IRC R703.8.6 and TMS 402 cap the spacing at 33 in on center (a common tighter spec is 24 in), at least 3/16 in diameter, immediately above the flashing. A 30 ft wall at 33 in is 12 weeps per line; the base course plus every shelf angle and lintel flashing above openings each need their own line. The weeps must sit directly on the flashing over a clear, un-mortar-clogged air space; the AHJ-adopted code and the wall detail govern. Distinct from the veneer ANCHOR count (brick-veneer-anchor-spacing).
Formula and source
weeps_per_line = ceil(wall_length_ft x 12 / max_spacing_in) + 1; total_weeps = weeps_per_line x round(flashing_lines).
IRC R703.8.6 and TMS 402 masonry-veneer weep-hole provisions, by name; the spacing cap and detail come from the adopted code.
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