Holdowns & Tension Ties
LTT/HTT Tension Ties
These products are available with additional corrosion protection. Additional products on this page may also be available with this option, check with Simpson Strong-Tie for details.
C-2011 © 2011 SIMPSON STRONG-TIE COMPANY INC. PRINTED 12/10
Model No.
Material (Ga)
Dimensions
Strap
Plate
W
L
CL
LTT19 3
16
3
13⁄4
191⁄8
13⁄8
LTT20B3
12
3
27⁄16
193⁄4
11⁄2
LTTI315
18
3
33⁄4
31
13⁄8
HTT4
11
—
21⁄2
12 3⁄8
13⁄8
HTT5
11
—
21⁄2
16
13⁄8
HTT5KT 7
11
1
21⁄2
16
13⁄8
⁄4
Holdowns & Tension Ties
Tension ties offer a solution for resisting tension loads that is fastened with nails. The entire line of tension ties has been tested and evaluated to the requirements of AC155. The HTT4 and HTT5 are the latest generation of tension ties. They feature an optimized nailing pattern which results in better performance with less deflection. Designed to meet new code standards, the HTT4 and HTT5 offer higher loads than their predecessors. The LTT19 Light Tension Tie is designed for 2x joists or purlins and the LTT20B is for nail- or bolt-on applications. The 3" nail spacing makes the LTT20B suitable for wood I-joists with 10dx1 1⁄2. The LTTI31 is designed for wood chord open web truss attachments to concrete or masonry walls and may also be installed vertically on a minimum 2x6 stud. MATERIAL: See table FINISH: Galvanized. May be ordered HDG; contact Simpson Strong-Tie. INSTALLATION: • Use all specified fasteners. See General Notes. • For use in vertical and horizontal applications. • To tie multiple 2x members together, the For tension ties, per ASTM test standards, Designer must determine the fasteners anchor bolt nut should be finger-tight plus required to join members without splitting 1 ⁄3 to 1⁄2 turn with a hand wrench, with the wood. consideration given to possible future • The Designer shall specify anchor bolt wood shrinkage. Care should be taken type, length and embedment. See SB and to not over-torque the nut. Impact SSTB anchor bolts on pages 36-40. wrenches should not be used. CODES: See page 20 for Code Reference Key Chart.
Load transfer plate washer not required
HTT5 LTTI31
LTT20B
(HTT4 similar)
(LTT19 similar)
U.S. Patent 5,467,570
These products are approved for installation with the Strong-Drive SD StructuralConnector screw. See page 30 for the correct substitution and SD screw size.
Seat Fasteners ThickFasteners ness Anchor Bolts 8-10dx11⁄2 5 3 5 1 ⁄16 ⁄2, ⁄8 or ⁄4 8-10d 10-10dx11⁄2 5 1 10-10d ⁄16 ⁄2, 5⁄8 or 3⁄4 2-1⁄2" Bolt 1 5 ⁄4 ⁄8 18-10dx11⁄2 18-10dx11⁄2 7 5 ⁄16 ⁄8 18-16dx21⁄2 18-SD #10x11⁄29 26-10dx11⁄2 7 5 ⁄16 ⁄8 26-10d 26-16dx21⁄2 7 5 ⁄16 ⁄8 26-SD #10x21⁄2
Allowable Tension Loads (160) DF/SP
SPF/HF
1310 1340 1355 1500 1625 1350 3610 4235 4455 4350 4670 50906 5445
1125 1150 1165 1290 1400 1160 3105 3640 3830 3740 4015 4375 5360
1. Allowable loads have been increased for wind or earthquake with no further increase allowed. Reduce where other loads govern. 2. Post design by Specifier. Tabulated loads are based on minimum 3"x3 1⁄2" post (in 3 1⁄2" wall). Post may consist of multiple members provided they are connected independently of the holdown fasteners. See pages 210-211 for common post allowable loads. 3. A standard cut washer is required under anchor nut for LTT19 and LTT20B when using 1⁄2" or 5 ⁄8" anchor bolts. No additional washer is required when using a 3⁄4" anchor bolt. 4. Deflection at Highest Allowable Tension Load includes fastener slip holdown deformation, and anchor bolt elongation for holdowns installed up to 4 1⁄2" above top of concrete. HTT4 and HTT5 may be installed raised up to 18" above top of concrete with no load reduction provided that additional elongation of the anchor rod is accounted for. 5. If the base of the LTTI31 is installed flush with a concrete or masonry wall, the allowable load is 2285 lbs. 6. Allowable tension load for HTT5 with a 3" bearing plate washer BP5/8-2 (sold separately) Min. installed in the seat of the holdown is 5295 Preservativefor DF/SP and 4555 for SPF/HF. treated 7. HTT5KT is sold as a kit with the holdown, BP 5⁄8-2 barrier may bearing plate washer and 26-SD #10x2 1⁄2 screws. be required 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) (see page 215 for details). 9. HTT4 with SD #10x1 1⁄2 screws achieves full load on a single 2x6 stud or joist. 10. FASTENERS: 10dx1 1⁄2 = 0.148 dia. x 1 1⁄2" long, 10d = 0.148" dia. x 3" long, 16dx2 1⁄2 = 0.162" dia. x 2 1⁄2" long, SD #10x2 1⁄2 = 0.161" dia. x 2 1⁄2", Vertical HTT4 Horizontal LTTI31 SD #10x1½ = 0.161" dia. x 1 1⁄2". Installation Installation
Deflection at Highest Allowable Load 0.180 0.157 0.195 0.185 0.183 0.193 0.086 0.123 0.112 0.120 0.116 0.135 0.103
Code Ref.
L19, IP2, F4
160 L19, IP2, F4 160
Hanger not shown for clarity
Horizontal HTT Installation
2"
Horizontal LTT19 Installation (LTT20B similar)
53