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Simpson Strong-Tie HDU Holdown

Updated Mar 25, 2026
Pre-engineered steel holdown connector for wood-frame shear wall anchorage. Resists uplift and overturning forces.

Simpson HDU series: pre-engineered steel holdowns for shear wall anchorage per IBC/IRC. Models: HDU2 (3,075 lb allowable), HDU4 (4,565 lb), HDU5 (4,910 lb), HDU8 (6,930 lb), HDU11 (9,775 lb), HDU14 (14,930 lb). Installation: bolt through rim joist/mudsill, anchor bolt into concrete foundation. 5/8 in or 7/8 in anchor bolts. Deflection data published for engineering. IAPMO/ICC-ES evaluation report ESR-2182. Materials: 14 gauge (HDU2/4/5) or 10 gauge (HDU8+) ASTM A653 G90 galvanized steel. Cost: $15-$60 per connector. Required at ends of braced wall panels per IRC R602.10 or engineered shear wall design. Alternative to cast-in-place embedded straps. CSI 06 05 23. Also: PAHD (concealed), MSTC (embedded strap).

TAGS
simpsonholdownshear-wallconnectorstructuralwood-frame
DETAILS
standard
ICC-ES ESR-2182
cost range
$15-$60
csi division
06 05 23
allowable loads
{"HDU2":"3075 lb","HDU4":"4565 lb","HDU8":"6930 lb","HDU14":"14930 lb"}
sustainability grade
B
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