Kaz's hands are clean (Situational Irony)
Many characters speculate about what is beneath Kaz's gloves (claws, flesh-burning curses, bloodstains) but Dirtyhands's hands are just clean, normal hands. This is ironic because the mythology around him is misplaced: "Dirtyhands" doesn't refer to the literal hands everyone is obsessed with; his hands are dirtied by his choices.
Turning to Rollins for help (Situational Irony)
Kaz spends the novel telling himself he doesn't need Inej, but when she's taken from him, he's willing to give up everything to get her back—and the only person who can help him is the one man he hates most in the world, Pekka Rollins. It's ironic that the man Kaz wants to take down "brick by brick" is the one man with the resources to help him; Kaz's long-term goal of destroying Rollins requires Rollins's help.
The House of the White Rose (Situational Irony)
The House of the White Rose brothel owner proclaims that the people who work there are all as sweet as the white roses that decorate the building; however, these roses have no odor, and the sweet smell is sprayed onto them artificially. This knowledge allies the reader with those who work in the brothel or the Barrel at large—we know the inner secrets, unlike the unsuspecting patrons; letting us in on the irony of the "sweet-smelling" roses stops us from being another mark.
Heist structure (Dramatic Irony)
The novel's heist framework immediately informs the reader's expectation of the plot. While characters make elaborate plans, the tropes of the novel require that those plans go awry; the reader watches the characters scheme, all the while knowing that there will be a twist that sends everything into chaos.
