Where spacing of openings is less than three times the diameter, multiple slab penetrations require one number-five top and bottom added trim bar all around the effective opening extending one foot six inches beyond the effective opening each side, with diagonal bars omitted. Effective opening outlines encompass closely spaced round penetrations maintaining minimum two-foot overall spacing or one-foot six-inch spacing depending on configuration and diameter. Diameter variables D and d define the sizing thresholds for effective opening boundaries.
WHERE SPACING OF OPENINGS IS < 3D OUTLINE OF EFFECTIVE OPENINGS, TYP NOTE: 1. ALL ABOVE CONDITIONS REQUIRE (1)#5 T&B ADDED TRIM BARS ALL AROUND THE EFFECTIVE OPENING EXTENDING 1'-6" BEYOND THE EFFECTIVE OPENING EACH SIDE, TYP (DIAGONAL BARS ARE NOT REQUIRED) D(OR d) = OPENING DIAMETER d d >d >d d 2'-0" MIN TYP d TYP >d 2'-0" MIN D >D d >d d 2'-0" MIN . 1'-6"
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