Lawes will replace Saracens lock George Kruis in the engine room for the Six Nations showdown with Scotland at Twickenham on Saturday.
Having recovered from the ankle surgery that forced him to miss the start of the Championship and proved his fitness during two matches for Saints, the 26-year-old will reprise a second row partnership with Dave Attwood last seen during the autumn.
And Rowntree believes England will benefit from his range of attributes when they seek a reaction to their subdued afternoon in Dublin.
“Courtney is a special player. He’s really maturing as a player and as a person. You can’t hide what he can bring to us physically,” said Rowntree.
“I’ve watched his last two games for Northampton and he’s played well. He’s played exceptionally well for us over the last year and he’s back to his best.
“Courtney is capable of the grunt work and that area of his game has significantly improved.
“We all know what he can do carrying-wise, athletically in defence and at line-out time, but I’m not worried about his lack of work-rate or having to balance him up.”
Dylan Hartley and Luther Burrell also start against Scotland, while Tom Wood is named among the replacements.
Alex Corbisiero, Calum Clark and Stephen Myler have all been released and will play no part in the game.