SPAX® PowerLags® T-Star Washer Head Wood Lag Screws

Base Part #: 458182()

Choose SPAX® PowerLags® T-Star Washer Head Wood Lag Screws. The low-profile, large diameter head design provides outstanding clamping force and improved aesthetics. Deep T-Star drive offers excellent bit engagement without requiring a “special” driver bit. Available in 1/4", 5/16”, and 3/8” diameters, and in lengths up to 10”. Buy SPAX T-Star Washer Head PowerLags and wood lag screws with HCR® high corrosion-resistant coating in bulk pails or in job-friendly package quantities (hex driver included) from wholesalers, dealers, and specialty distributors or retail hardware and home improvement stores near you.

Kick failures to the curb with American-made, rigorously tested wood-to-wood structural fasteners. Get the Full Story

Description

SPAX® T-Star Washer Head construction fasteners with HCR® coating are intended for wood-to-wood connections in exterior structural applications when attaching treated lumber components. These fasteners are designed with a low profile large diameter wafer head for applications requiring additional surface area under the head for superior pull-down force. Ideal for deck ledger attachment and multi-ply beam applications.

Material & Coating

Cold-rolled “carbon steel” wire heat treated to Grade 5 durability and plated with an HCR® (High Corrosion Resistance) double barrier coating. “HCR” is tested and recognized for use in ground contact pressure treated lumber for exterior, freshwater general construction applications (e.g. AWPA UC1-UC4A, UCFA)
Note: We are transitioning from green to black HCR during mid-June 2022 - New Color Matches Trending Exterior Projects!

SPAX® POWERLAGS®

SPAX PowerLags require no pre-drilling and drive faster and easier than conventional lags and other structural lag screws. We offer the largest selection of code-recognized structural wood-to-wood fasteners in the industry. Featuring SPAX patented thread technology and HCR high corrosion resistant coating, our T-Star washer head and PowerLags collection can be used for interior or exterior applications, including treated lumber.

  • IRC / IBC Code Compliant DrJ TER No. 1912-07 Structural Fastener Properties
  • DrJ Technical Evaluation Reports (TER No. 1711-01; Deck Ledger Attachment and TER No. 1802-03; Multi-Ply; Sawn lumber assemblies and engineered wood - LVL, PSL and LSL assemblies)
  • Grade 5 durability
  • No pre-drilling required (1/4" and 5/16")
    Note: Lead hole of 11/64" (0.172") diameter is required for 3/8"
  • Patented thread serrations require up to 40% less driving torque to increase installation speed while helping prevent cracking in logs
  • Built-on washer head designs eliminate the need and extra cost of a separate washer
  • Fastener length stamp on the head provides convenient identification without measuring and aids on-site inspections

Choose SPAX PowerLags structural wood to wood screws with built-on washer design in a variety of screw styles, including Hex head, T-Star, and multiple coating options. Request a sample pack of SPAX PowerLags today and build strong connections on the job site. Need something stronger? Shop our PowerLags collection designed for timber frame and log home construction.

TYPICAL EXTERIOR APPLICATIONS

• Multi-ply LVL beam assembly

• Multi-ply girder truss assembly

• Exterior treated lumber pergolas & gazebos

• Landscaping timber

• Outdoor furniture

• Exterior fencing posts

• Exterior out buildings

• Deck ledger to residential band joist attachment

For CAD documents, please see Technical Documents.

SizeDrive/Bit SizeThreadAvailable Pkg. Options
Retail PaxLarge Retail Pax1 lb. Box3 lb. Box5 lb. BoxIndividualProject PaxContractor PaxBulk Pail
1/4" x 2-1/2"T-30Partial1+1250500
1/4" x 3"T-30Partial1+1250500
1/4" x 3-1/2"T-30Partial1+1250500
1/4" x 4"T-30Partial1+1250500
1/4" x 4-1/2"T-30Partial1+1250500
1/4" x 5"T-30Partial1+1250500
1/4" x 6"T-30Partial1+1250500
5/16" x 3"T-40Partial1+1250250
5/16" x 3-1/2"T-40Partial1+1250250
5/16" x 4"T-40Partial1+1250250
5/16" x 4-1/2"T-40Partial1+1250250
5/16" x 5"T-40Partial1+1250250
5/16" x 6"T-40Partial1+1250250
5/16" x 6-3/4"T-40Partial50250
5/16" x 8"T-40Partial1+1250150
5/16" x 10"T-40Partial1+1250150
5/16" x 12"T-40Partial1+50150
3/8" x 5"T-50Partial1+1225150
3/8" x 6"T-50Partial1+1225150
3/8" x 8"T-50Partial1+150
3/8" x 10"T-50Partial1+150
PDF Icon PowerLags T-Star Washer Head HCR SPEC Sheet (2 MB) PDF Icon SPAX POWERLAGS Engineering Product Submittal (4 MB) PDF Icon DrJ TER No. 1912-07 POWERLAGS Fastener Properties 7-27-2022 (819 KB) PDF Icon DrJ TER 1711-01 Rev 5-3-2022 Deck Ledger Attachment Using SPAX PowerLags (590 KB) PDF Icon SPAX Technical Bulletin Deck Ledger Attachment Form S-1803 Rev 7-22 (861 KB) PDF Icon DrJ TER No. 1802-03 Rev 3-9-2021 Multi-Ply (Sawn Lumber and Engineered Wood: LVL, LSL and PSL) (517 KB) PDF Icon SPAX Technical Bulletin Multi-Ply Form S-2003 Rev 8-2022 (2 MB) PDF Icon SPAX Bit Center Options (901 KB) PDF Icon SPAX Materials & Coatings (1 MB) PDF Icon 1/4”(.250) Washer Head T-Star PowerLags 2-D Screw Size Reference Drawing (PDF) (264 KB) PDF Icon 1/4”(.250) Washer Head T-Star PowerLags Full Scale CAD Files (PDF) (112 KB) PDF Icon 1/4”(.250) Washer Head T-Star PowerLags Full Scale CAD Files (DWG) (150 KB) PDF Icon 1/4”(.250) Washer Head T-Star PowerLags Full Scale CAD Files (DXF) (613 KB) PDF Icon 5/16”(.312) Washer Head T-Star PowerLags 2-D Screw Size Reference Drawing (PDF) (271 KB) PDF Icon 5/16”(.312) Washer Head T-Star PowerLags Full Scale CAD Files (PDF) (133 KB) PDF Icon 5/16”(.312) Washer Head T-Star PowerLags Full Scale CAD Files (DWG) (215 KB) PDF Icon 5/16”(.312) Washer Head T-Star PowerLags Full Scale CAD Files (DXF) (1 MB) PDF Icon 3/8”(.375) Washer Head T-Star PowerLags 2-D Screw Size Reference Drawing (PDF) (261 KB) PDF Icon 3/8”(.375) Washer Head T-Star PowerLags Full Scale CAD Files (PDF) (103 KB) PDF Icon 3/8”(.375) Washer Head T-Star PowerLags Full Scale CAD Files (DWG) (125 KB) PDF Icon 3/8”(.375) Washer Head T-Star PowerLags Full Scale CAD Files (DXF) (465 KB)