Double the strength,
10x the stiffness.
Reduce fastener count and installation labor while increasing strength and stiffness in your timber-to-timber connections with Sharp Metal.
In mass timber construction, connections are often the constraint. You hit minimum spacing limits, run out of edge distance, and still need more capacity.
Sharp Metal is a 0.03 in. (0.75 mm) martensitic stainless steel strip with hooks on both surfaces. The hooks engage the wood fiber under compression and add shear capacity and stiffness to the connection independent of the screws themselves. In practice, this means you can either get twice the resistance from the same number of fasteners, or maintain the same resistance with half the fasteners.
Double the shear resistance of a screw-only connection by adding Sharp Metal to the shear plane
204% flexural rigidity in full-scale composite beam testing vs. screws alone, closing 75% of the performance gap to a rigid epoxy glue bond (ETA-24/0058, 26.2 ft (8 m) span GL24h beam with CLT panel)
Matches 0.79 in. (20 mm) STA dowel performance using 0.31 in. (8 mm) self-drilling TBS screws with no pre-drilling required (Rothoblaas full-scale bending test, 20 ft (6.1 m) composite beam)
Hooked plate helps resist splitting of the wood fiber, allowing reduced fastener edge distances and minimum spacing in geometrically constrained connections
Sharp Metal offers a solution.
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Unmatched performance and durability
A shear connector that adds capacity without adding fasteners
Sharp Metal is a 0.03 in. (0.75 mm) martensitic stainless steel strip with hooks on both surfaces. Installed in the shear plane between timber members, the hooks engage the wood fiber under compression and transfer shear forces independent of the screws.
A dry connection that performs like an adhesive bond
Full-scale composite beam testing (26.2 ft (8 m) span, GL24h beam with CLT panel) showed Sharp Metal with screws achieved 204% of the flexural rigidity of screws alone. That closes 75% of the performance gap to a rigid epoxy bond.
Replaces large-diameter dowels with self-drilling screws
In full-scale bending tests, Sharp Metal with 0.31 in. (8 mm) TBS screws matched the composite action of 0.79 in. (20 mm) STA dowels. No pre-drilling required. Smaller fasteners, equivalent performance.
ETA certified with over six years of development
Over 12,000 tests across density, moisture, and grain orientation variables. ETA-24/0058. Covering solid timber, glulam, CLT, LVL, and softwood plywood.
Resources and technical data
Browse our technical resources or talk to our engineers to get more specified data.
Technical Data Sheets
ETA Certification
BIM.ifc File
BIM.rfa File
Sharp Metal DOP
Advanced Shear Reinforcement for Mass Timber by Roland Maderebner
Roland discusses the advantages for engineers in using Sharp Metal for timber-to-timber connections.
Long-Span Composite Mass Timber Cassette Floors with SHARP METAL
Dr. Pang from Clemson University discusses his ongoing research on long-span cassette floors using GripMetal.
Learn more about the founding team behind Sharp Metal and GripMetal™
Learn more about the team behind the vision to improve and enhance mass timber construction.
Product Gallery
Frequently asked questions
Below are a list of frequently asked questions, if you have additional questions - you can speak with one of our engineers by submitting the form at the bottom of this page.
What makes Sharp Metal different from adding more screws?
Screws are limited by minimum spacing and edge distance requirements. Beyond a certain density, adding more fasteners can increase the risk of splitting the timber. Sharp Metal adds shear capacity and stiffness to the connection through mechanical interlock in the shear plane, independent of the fastener count. You increase the performance of the connection without increasing the number of penetrations in the wood.
Can I use Sharp Metal in North America without ICC-ES approval?
Yes. Rothoblaas works directly with the engineer of record to develop project-specific documentation using the ETA data and accepted mechanics principles. This documentation can support AHJ review for the specific application. The process is generally straightforward on most project types, though high-seismic zones may require additional review.
What timber products is Sharp Metal compatible with?
The ETA covers softwood in solid timber, glulam, CLT, LVL, and plywood. Service classes 1 and 2. Minimum connected element thickness of 2.36 in. (60 mm).
How do I get started if I have a project in mind?
Contact Rothoblaas’s North American team using the form on this page. They will review your application, provide design guidance, and coordinate engineering support. For new or untested applications, Fast + Epp’s Concept Lab may run a proof-of-concept test program.
Spec sharp metal in your North American project
For projects in North America, Rothoblaas works directly with the engineer of record to develop application-specific guidance using ETA data and support the documentation needed for authority having jurisdiction (AHJ) review. Fill out the form to speak with our North American engineers.