Choose from 3"or 5" widths and 3/8", ½", or 9/16" thickness in random lengths up to 42". Engineered plank floors 3/8" thick and up may be floated, glued, nailed down or stapled down above, on or below ground level over an OSB board, plywood or concrete subfloor. Once installed, the single board surface width gives the appearance of a solid wood floor.