HD Holdowns

HD holdowns provide a bolted holdown solution.

NEW! The HD19 is a high-capacity bolted holdown designed for applications that require loads beyond the capacity of the HDU series holdowns. The HD19 can be installed back-to-back when maximum capacity is needed or when eccentricity is an issue.

The HD9, HD12 and HD19 holdowns are self-jigging, ensuring that the code required minimum of seven bolt diameters from the end of the post is met. The HD5 and 7 must be raised such that the seven bolt diameter minimum from the end of the post is maintained.

Material: See table.

Finish: Simpson Strong-Tie® gray paint.

Installation:

Use all specified fasteners. See General Notes.
For use in vertical and horizontal applications.
HD holdowns are required to be installed such that the bottom stud bolt is a minimum of seven bolt diameters from the end of the post (2005 NDS, Section 11.5.1) which is indicated by the dimension in the drawing labeled (HB). HD9, 12 and 19 holdowns are self-jigging, ensuring that the code required minimum of seven bolt diameters from the end of the post is met. The HD5 and 7 must be raised such that the seven bolt diameter minimum from the end of the post is maintained (refer to table for HB dimension).
Bolt holes shall be a minimum of 1/32" to a maximum of 1/16" larger than the bolt diameter (per NDS, section 11.1.2).
Standard cut washer required between nut and base when using smaller diameter anchor bolts (see footnote 11).
Stud bolts should be snugly tightened with standard cut washers between the wood and nut (BP’s are required in the City of Los Angeles).
The Designer must specify anchor bolt type, length, and embedment. See SB and SSTB Anchor bolts.
To tie multiple 2x members together, the Designer must determine the fasteners required to join members
to act as one unit without splitting the wood (See SDS Screw information.) .
Refer to Anchor Designer Software™ for ACI 318 for anchoring solutions.

For holdowns, per ASTM test standards, anchor bolt nut 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 to not over-torque the nut. Impact wrenches should not be used.

Allowable loads have been increased for wind or earthquake load durations wth no further increase allowed; reduce where other load durations govern.
HD12 and HD19 require a minimum 4x8 (in a 3 1/2" wide shearwall) or 6x6 nominal post to ensure the tension load carrying capacity of the critical net section meets the holdown capacity. Designer to evaluate combined bending and tension stresses.
HB is the required minimum distance from the end of the stud to the center of the first stud bolt hole. End distance may be increased as necessary for installation (see General Notes). Tension values are valid for holdowns installed flush to, or raised off of, the sill plate provided that the minimum HB distance is maintained.
The Designer must specify anchor bolt type, length and embedment. See SB and SSTB Anchor Bolts. Refer to Anchor Designer Software™ for ACI 318 for anchoring solutions.
Lag bolts will not develop the listed loads.
Deflection at Highest Allowable Tension Load includes fastener slip holdown
elongation, and anchor bolt elongation (L = 8"). Additional elongation of anchor bolts shall be accounted for by the Designer when holdowns are raised higher than 8".
Structural composite lumber columns have sides that show either the wide face or the edges of the lumber strands/veneers. Values in the tables reflect installation into the wide face. See technical bulletin T-SCLCOLUMN for values on the narrow face (edge).
To achieve published loads, machine bolts shall be installed with the nut on the opposite side of the holdown (see drawing). If reversed, the Designer shall reduce the allowable loads shown per NDS requirements when bolt threads are in the shear plane.
For SPF/HF allowable loads use 0.85 of the DF/SP allowable loads.
Tabulated values may be doubled when the HD holdown is installed on opposite sides of the wood member. The Designer must evaluate the capacity of the wood member and the anchorage.
Standard cut washer required under anchor nut for HD5 with 5/8" anchor and HD7, HD9 and HD12 with 7/8" or 1" anchors. HD19 requires a cut washer with 1 1/8" anchors.
Post design shall be by Designer. Tabulated loads are based on 3 1/2" wide post minimum.

Download the Simpson AutoCad Menu, which allows you to insert Ortho views directly into your AutoCAD drawing.

	ORTHOGRAPHIC	PERSPECTIVE
HD	None for this model	None for this model
HD12	None for this model	None for this model
HD15	HD15: DWG \| DXF HD15 front view: DWG \| DXF HD15 left view: DWG \| DXF HD15 right view: DWG \| DXF HD15 top view: DWG \| DXF	HD15: DWG \| DXF
HD19	HD19: DWG \| DXF HD19 front view: DWG \| DXF HD19 left view: DWG \| DXF HD19 right view: DWG \| DXF HD19 top view: DWG \| DXF	HD19: DWG \| DXF
HD5	None for this model	HD5 Joist to Joist: DWG \| DXF
HD7	None for this model	None for this model
HD9	None for this model	None for this model

					Legacy Reports
	IAPMO ES ER	ICC-ES ESR	CITY OF LOS ANGELES	STATE OF FLORIDA	ICC-ES NER	ICC-ES ER	ICC-ES ES
HD	See specific model numbers for code listings.
HD12	ER-143			FL12708
HD15						ER-5708
HD19	ER-143			FL12708
HD5	ER-143			FL12708
HD7	ER-143			FL12708
HD9	ER-143			FL12708