Hidden fastener formed in situ during attachment of sheathing onto a support member

A hidden fastener for attaching laterally adjacent sheathing members having side grooves to a support member, comprising:

• a cross member having a generally flat body defining a lateral plane and having two opposing side edges extending between first and second opposite ends, the first end having at least one downwardly projecting prong and being configured for engagement with the groove of a first sheathing member, and the second end having a generally upwardly angled wing and being configured for engagement with the groove on a second sheathing member, the body defining a hole extending through the lateral plane;
• and
• an elongate anchoring member comprising a head and a shank, wherein
• each end of the cross member is configured to engage the groove of an adjacent sheathing member and a portion of the anchoring member shank is configured to be driven through the cross member hole into the support member to rigidly attach the first sheathing member to the support member by engagement between the cross member first end with the first sheathing member groove.