JOISTS is a playable word

joist Scrabble® Dictionary

verb
joisted, joisting, joists
to support with horizontal beams
23 Playable Words can be made from "JOISTS"
   2-Letter Words (9 found)
   3-Letter Words (7 found)
   4-Letter Words (5 found)
   5-Letter Words (1 found)
   6-Letter Words (1 found)