Stress plate with angled hole

A fastener assembly for securing relatively soft insulation to a solid base, comprising:

• a fastener having a head, a tip and a threaded portion located between said tip and said head;
• a stress plate having a generally planar main body;
• a generally central hole on said main body configured for receiving the fastener;
• said hole being defined by a depression generally centrally formed in said main body, in defining said hole, said depression has a first side and a second side, said second side is shorter than said first side, said hole having first and second side walls, each located between said first and second sides and wherein the fastener has a root diameter and the thread has an outer diameter, said first side wall engages the root diameter and said second side wall engages the outer diameter;
• at least one strengthening corrugation formed in said plate to surround said depression;
• and
• said plate being configured so that said hole is planar, yet angled relative to a vertical axis of said plate for accommodating said threaded portion of said fastener so that said fastener is maintained in a generally perpendicular orientation to said main body upon the engagement of said threaded portion of the fastener in said hole.