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CTUD Coupling Take-Up Device

CTUD

The CTUD is a combination coupler nut and take-up device. It compensates for the slack that develops in the continuous rod system resulting from the shrinkage of wood members. It will accommodate up to 1" of movement and is available in standard and reducing sizes for 5/8", 3/4", 7/8", 1" and 1 1/8" diameter Strong-Rod™ threaded rod or other threaded rod

Key Features

  • Design of the CTUD eliminates parts and simplifies installation.
  • Easy installation saves time.
  • Witness Holes™ allow for easy inspection to verify proper thread engagement.
  • The positive stop at each end ensures that the rod is threaded to the proper depth.

Material

  • ATSM A311 Class B, Grade 144

Finish

  • Corrosion-resistant finish

Installation

Important: Do not remove the activation pin until the isolator nut is installed at the level above.

  1. Thread the specified CTUD (wider end up) onto the embedded anchor (in first-floor applications) or the Strong-Rod™ threaded rod from the level below. Position so that the activation pin faces out for easy access.
  2. Insert 8d nail into witness hole. Manually rotate threaded rod into CTUD from above until it touches the inserted nail. Remove nail and rotate the rod until visible in the witness hole or a nail can no longer be inserted in the hole. No tools required. Do not overtighten.
  3. Secure Strong-Rod threaded rod at the level above with specified bearing plate and Isolator Nut. Attach Isolator Nut to sill plate above with #8 x 3" screw (provided).
  4. Remove shrink wrap from CTUD. Remove activation pin after level above is secured with Isolator Nut and prior to covering.
  5. Continue system installation at each level until the run is complete.

Related Literature

Load Tables

Model No. Threaded Rod
Diameter
(in.)
W
(in.)
L
(in.)
Allowable Tension
Capacity
(lbs.)
Deflection
for Seating, ΔR
(in.)
Deflection
at Allowable Load, ΔA
(in.)
CTUD55 5/8 - 5/8 1 7/8 5 15,520 0.004 0.006
CTUD65 3/4 - 5/8 2 5 1/2 31,795 0.003 0.060
CTUD66 3/4 - 3/4 2 5 1/2 31,795 0.003 0.060
CTUD75 7/8 - 5/8 2 5 1/2 31,795 0.003 0.060
CTUD76 7/8 - 3/4 2 5 1/2 31,795 0.003 0.060
CTUD77 7/8 - 7/8 2 5 1/2 31,795 0.003 0.060
CTUD87 1 - 7/8 2 1/2 6 1/8 55,955 0.003 0.033
CTUD88 1 - 1 2 1/2 6 1/8 55,955 0.003 0.033
CTUD97 1 1/8 - 7/8 2 1/2 6 1/8 55,955 0.003 0.033
CTUD98 1 1/8 - 1 2 1/2 6 1/8 55,955 0.003 0.033
CTUD99 1 1/8 - 1 1/8 2 1/2 6 1/8 55,955 0.003 0.033
  1. Allowable tension capacities are for CTUD only and are based on ICC-ES ESR-2320.
  2. No further steel stress increase allowed.
  3. Thread specification for threaded rod must be UNC Class 2A per ANSI/ASME B1.1.
  4. Deflection at demand load may be calculated by (demand/capacity)*ΔA.
  5. Total device deflection = ΔTRA(PD/PC).

Code Reports

Part IAPMO UES ER ICC-ES ESR City of Los Angeles State of Florida
CTUD55 ESR-2320 RR25643 FL10007
CTUD65 ESR-2320 RR25643
CTUD66 ESR-2320 RR25643
CTUD75 ESR-2320 RR25643 FL10007
CTUD76 ESR-2320 RR25643
CTUD77 ESR-2320 RR25643 FL10007
CTUD87 ESR-2320 RR25643
CTUD88 ESR-2320 RR25643
CTUD97 ESR-2320 RR25643 FL10007
CTUD98 ESR-2320 RR25643
CTUD99 ESR-2320 RR25643 FL10007

Drawings

Part Orthographic Perspective
CTUD55None None
CTUD65None None
CTUD66None None
CTUD75None None
CTUD76None None
CTUD77None None
CTUD87None None
CTUD88None None
CTUD97None None
CTUD98None None
CTUD99None None