HDC10/4-SDS2.5 Concentric Holdown

*For further description please see Simpson Strong-Tie Wood Construction Connectors Catalog.

**Click Load Table icon for size & fastening requirements.

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HDC Concentric Holdown

The unique design of the HDC holdowns eliminate eccentricity. They install with Simpson Strong-Tie® Strong-Drive® SDS screws (included) to reduce slip and provide a greater net section area of the post compared to bolts.

Material: 10 gauge strap

Finish: Galvanized strap, aluminum base

Installation:

•Use all specified fasteners. See General Notes.

•Install on concrete.

•For use in vertical and horizontal applications.

•Sized for 2-2x, and 4x. Center 2-2x posts on holdown.

•Uses SDS screws supplied with the holdowns to ensure proper fasteners are used.

•Slot in the seat allows for 3/8" of adjustment perpendicular to plate.

•Cut washer required between base and anchor nut. HDC10 models use narrow cut washer with outside diameter of 1 3/4".

•Witness slot in the base to inspect the nut.

•Maximum anchor bolt height above concrete is 2 1/8".

•To tie multiple 2x members together, the Designer must determine the fasteners required to join members without splitting the wood.

•Aluminum standoff cannot be in contact with preservative-treated wood.

•SDS screws install best with a low speed high torque drill with a 3/8" hex head driver.

•Refer to Anchor Designer Software™ for ACI 318 for anchoring solutions.

For holdowns, per ASTM test standards, anchor bolt nuts should be finger-tight plus 1/3 to 1/2 turn with a hand wrench, with consideration given to possible future wood shrinkage. Care should be taken not to over-torque the nut. Impact wrenches should not be used.