US Patent 8408856 Self-drilling fastener

A fastener mountable to a rigid substrate such as a fiber cement panel and also mountable to the panel and an underlying support, such as a metal or wooden stud. The fastener may include a drilling portion having a reaming portion for reaming out the material within the panel, a fastening portion for engaging the panel and, if encountered, the underlying support, and a tapered portion between the drilling and fastening portions. The drilling portion may have a length generally equal to, or slightly longer than, a length of the panel so that reaming out of the panel may be completed before engagement of the fastener threads with the interior of the panel begins.