Resuming on 72 after play was called early on day one, Root contined his push with little fuss in spite of a better bowling effort from the hosts who were also aided by a more inconsistent surface.
Root watched Harry Brook (84), Ben Stokes (0) and Jamie Smith (46) fall at the other end, though carried on to walk off at lunch on 138 not out.
In the middle session of the day Root reached the 150 mark, with his innings only ended on 160 by an athletic caught and bowled by Michael Neser.
