HDB Bolted Holdown
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The HDB is designed to provide loads for intermediate-load-range shearwalls, braced-wall panels and lateral applications in wood construction. This bolted holdown is installed with bolts into studs or columns and offers low-deflection performance for a range of load requirements. The HDB is suitable for back-to-back applications where eccentricity is a concern.
- Installed after the placement of concrete and framing is in place
- Can be installed directly on the sill plate or raised above it
- Self-jigging, ensuring the code-required minimum of seven bolt diameters from the end of the post when installed flush with the sill plate
- See table
- Galvanized or HDG
- See General Notes for Holdowns and Tension Ties
- Bolt holes shall be a minimum of 1/32" to a maximum of 1/16" larger than the bolt diameter (per 2015/2018 NDS, section 188.8.131.52)
- Stud bolts should be snugly tightened with standard-cut washers between the wood and nut (BPs are required in the City and County of Los Angeles)
Product Information Table
|Model No.||Base/Seat Thickness (in.)||Ga.||HB (in.)||SB (in.)||W (in.)||H (in.)||B (in.)||CL (in.)||SO (in.)||Coating/Material||Packaging Qty.|
|HD3B||–||12||4 3/4||2 1/2||2 1/2||8 5/8||2 1/4||1 5/16||3/8||Zinc Galvanized, G90||1|
|HD3BHDG||–||12||4 3/4||2 1/2||2 1/2||8 5/8||2 1/4||1 5/16||3/8||Hot-Dip Galvanized||1|
|HD5B||3/16||10||5 1/4||3||2 1/2||9 3/8||2 1/2||1 1/4||2||Zinc Galvanized, G90||1|
|HD5BHDG||3/16||10||5 1/4||3||2 1/2||9 3/8||2 1/2||1 1/4||2||Hot-Dip Galvanized||1|
|HD7B||3/16||10||5 1/4||3||2 1/2||12 3/8||2 1/2||1 1/4||2||Zinc Galvanized, G90||1|
|HD7BHDG||3/16||10||5 1/4||3||2 1/2||12 3/8||2 1/2||1 1/4||2||Hot-Dip Galvanized||1|
|HD9B||3/8||7||6 1/8||3 1/2||2 7/8||14||2 1/2||1 1/4||2 3/8||Zinc Galvanized, G90||1|
|HD9BHDG||3/8||7||6 1/8||3 1/2||2 7/8||14||2 1/2||1 1/4||2 3/8||Hot-Dip Galvanized||1|
These products are available with additional corrosion protection.
- To achieve published loads, machine bolts shall be installed with the nut on the opposite side of the holdown. If this orientation is reversed, the designer shall reduce the allowable loads shown per NDS requirements when bolt threads are in the shear plane.
- All references to bolts are for structural quality through bolts (not lag screw or carriage bolts) equal to or better than ASTM A307, Grade A.
Code Reports & Compliance