Technical Specifications

53
Holdowns
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TD / TDX Holdowns
TD – Different welded congurations and sizes achieve a great deal of
versatility within the TD series.
TDX – The TDX2 and TDX5 feature formed designs, all others
are welded. All are self-jigging.
All models, except TD2, TD5, and TD7, feature a self-jigging design
with code required end distances built in. (End distance = 7 bolt
diameters from the top of the sill to the center of the rst bolt hole
in the studs or post.)
Materials: See chart
Finish: TDX2-TZ – G-185 galvanizing; All others – USP primer
Codes: See page 11 for Code Reference Key Chart
Patents: #5,092,097 — TDX2
Installation:
• Use all specied fasteners. See Product Notes, page 17.
• Do not use lag bolts. Washers are not required for anchor bolts or
between holdown and bolt hex head, but standard washers should
be used against stud or post under the nut. See page 36 for BP/LBP
Bearing Plates.
• Bolt holes should be a minimum of 1⁄32" to a maximum of 1⁄16"
larger than the bolt diameter (as per NDS
®
specications).
• See pages 34-35 for STB Anchor Bolt section for anchorage
options. A design professional may specify alternate anchorage with
conventional anchor bolts.
• A design professional shall determine the adequacy of the stud to
resist published loads. When installing to multi-ply 2x studs, the
designer must specify the fasteners required to bind the plies together
and resist splitting.
• Self-jigging models are designed to provide the required minimum end
distance of 7 bolt diameters from the bottom of the stud or post to the
centerline of the rst bolt hole.
• Tighten anchor bolt nuts to nger tight, plus 1/3 to 1/2 additional turns
with a wrench. Wood members may shrink over time; if possible, nut
tightness should be checked periodically. To prevent loosening of the
anchor bolt nut during critical loading, use a locking nut or tighten a
second nut over the rst to lock nuts in place.
• If used to anchor a built-up post, such as a double 2 x 4, the post
component shall be designed to act as a single unit. Holdown fasteners
specied shall not be considered to attach multiple plies together.
• Bolts must be ordered separately. See page 24 for available sizes.
Typical TDX2-TZ
installation
Holdown installation
between oors
Typical TDX2-TZ
back-to-back
installation
Typical TD15
installation
TDX6
TDX2-TZ
Typical TDX6
installation
Moisture barrier
may be required
Use bearing plates
between nut and stud
BP's required by the
City of Los Angles.
Check with your local
building code. (NDS
section 11.1.2.3
requires a metal plate,
metal strip, or min. of a
std. cut washer.
Washer required
under anchor
bolt nut
TD15 = 3-3/8"
TD9 & TD12 = 3-1/2"
End distance
Wall stud
Threaded
rod
H
H
D
D
W
W
CL
CL
3-1/2"
3-1/2"
End
dist.
End
dist.
9/16"
Continued on next page
Holdowns
9/16"