so that the nails are frictionally locked between the vertical legs in addition vertically arranged wood strips interconnect the chords at the opposite ends of the joist application_number US 13498480 A description fig1 5 depict the preferred form of the invention as shown in fig1 and 2 the joist 10 is formed with an upper chord 11 and a lower chord 12 each of which is made of a pair of angle iron strips 13 and 14 the right angle cross section strips 13 and 14 are arranged with a horizontal leg 15 and a vertical leg 16 with the horizontal legs of each pair of strips in alignment and the vertical legs spaced apart a short distance to provide a space or gap 17 between the strips the upper and lower chords are interconnected by sheet metal connectors 20 shown individually in fig4 preferably the connectors are v shaped stamped sheet metal structures with two diagonally extending legs or webs 21 the lower ends of each web are provided with flat enlarged end portions 22 and the other ends of the webs are joined at a common junction portion 23 which also is flat the webs are each preferably formed with an elongated stamped rib 24 extending its length as shown in fig4 and 5 in addition.