17 two runner beam sections with one cross beam section as at 18 one runner beam section with two cross beam sections as at 19 and two runner beam sections with two cross beam sections as at 20 about the outer perimeter of the subceiling the intersection spacers exhibit outwardly facing protrusions 21 having the appearance of short extensions of the beams bottom caps 22 with decorative panels 23 are visible at the undersides of the intersection spacers 12 fig2 shows the arrangement and assembly of the intersection spacers 12 identical half shells 30 when assembled together form a core body which in turn when assembled together with a top plate 31 will become an intersection spacer 12 each half shell has a pair of boss supported upwardly extending pins 32 at the top end a row of small seam alignment pins 34 and a larger boss supported bottom alignment pin 35 on one mating edge a corresponding row of seam alignment holes 36 and a boss enclosed bottom alignment hole 37 on the other mating edge the half shells 30 are each shaped to have inverted vertical corner edges 40 forming a rectangular protrusion 21 and two rectangular half protrusions 42 these are provided with a protrusion floor 43 at the bottom of the the protrusion floor depending at the bottom of the half shell is a skirt 45 formed through.