As with many hardwoods Hickory can split if the proper installation tools are not used.
Fortunately we do address these specific concerns in our installation instructions in detail;
[EXOTIC WOOD NAILING TIPS]:
Tongue fracture and surface dimpling during installation is common and can be minimized by (1) Installing the flooring in proper lighting (2) using the correct nail thickness, (3) using the recommended shoe adaptor, or (4) changing the angle of nail entry.
To further reduce the occurrence of surface dimpling and tongue fracture the use of flooring nailers with a thinner 18-20 gage cleat nail may be needed for the harder exotics species. In addition, many installers will sometimes temporarily adjust the nailer angle by applying layers of duct tape to the bottom foot plate of the nailer. The use of an over-size base or foot plate to distribute the nailing force is encouraged. If however, surface dimpling or tongue fracture occurs when nailing the denser species, drilling pilot holes and hand nailing may be required.
Use caution when fastening the harder exotics with Staplers. The drive bar in Staplers are wider and if fasteners are overdriven can act like a wood chisel, splitting tongues. Do not mix fasteners when nailing. Staples and cleats hold differently when mixed can result in irregular seasonal gapping and or movement. When face or top nailing, pick areas of the grain or pattern that would best hide touch-up fillers.
If nailers prove difficult fastening the lower profile 3/8”or 5/16” floors, many installers will use 100% urethane wood floor adhesives rather than nailers, especially with the more brittle species like; Australian Cypress, Brazilian Walnut, Teaks. Do not use significantly bowed, crooked or twisted boards. Use a wood spline or slip tongue whenever a change of board direction
is needed, wood splines should be both glued and nailed into place. Forcing or pounding floor boards together with a rubber mallet during assembly may burse or damage unprotected board edges.
You can find complete installation instructions on the product page by clicking on the specs tab and then clicking on - Installation Guide.pdf
Thank you for your question.
Answered on 11/22/2011 by customer care 2