Buttler comes in for Ben Duckett, who has been dropped, while Woakes replaces the injured Stuart Broad.
"Stuart is definitely out," Alastair Cook confirmed. "And Chris Woakes is definitely in."
Cook also confirmed that Zafar Ansari was not fit for selection but delayed naming a full side until he had taken the chance to inspect the pitch and decide whether a third spinner or fourth seamer would be more appropriate. It looks likely though that Gareth Batty, the offspinner, will come into the side in place of Ansari.
Moeen Ali is to be promoted to No. 4 in the batting order and Jonny Bairstow to No. 5. Buttler will bat at No. 7. That means Moeen will have batted at every position in the top nine for England in Test cricket except at No. 3, which is where he bats for Worcestershire.
More to follow