Composite floor beam

A composite floor beam configured for use in a workpiece structure having at least one floor and at least one ceiling and utilities therein, the composite floor beam comprising:

• an upper part composed of wood, the upper part extending substantially along a length of the beam;
• and
• a lower part composed of steel, the lower part extending substantially along the length of the beam,
• wherein the upper part comprises an upper surface and a lower surface,
• wherein the lower part comprises an upper surface and a lower surface,
• wherein the upper surface of the upper part is configured to be positioned horizontally to support the workpiece floor above,
• wherein the upper surface of the upper part is parallel to the lower surface of the lower part,
• wherein the lower surface of the lower part is configured to be positioned horizontally for attachment to the workpiece ceiling below,
• wherein at least one of (i) the lower surface of the upper part has an irregular shape defined by a non-uniform distance extending between the lower surface of the upper part and the upper surface of the upper part that varies along an entire length of the upper part, and (ii) the upper surface of the lower part has an irregular shape defined by a non-uniform distance extending between the upper surface of the lower part and the lower surface of the lower part that varies along an entire length of the lower part, and
• wherein the lower surface of the upper part and the upper surface of the lower part define apertures therebetween for the workpiece utilities, the apertures passing from a first side of the beam to a second side of the beam transverse to a direction of the length of the beam and between distal ends of the beam.