Griet is hired because she can work without moving or disrupting anything (Situational Irony)
The reason the Vermeer family initially seeks a maid is because other individuals upset Vermeer by altering the layout of the studio when they enter to clean it. Vermeer notices Griet's attention to visual detail when she is chopping vegetables, encouraging him to hire her, and he is proven right when Griet is able to meticulously clean the studio while replacing every object exactly as it was, making her presence virtually undetectable. Yet despite Griet's skill at being unobtrusive, she ends up creating chaos within the household and throwing the emotions of the family into disarray by inspiring desire in Vermeer and jealousy in Catharina. Ironically, the girl who is supposed to not change anything changes the entire family dynamic in ways that linger even after her departure.
Griet's modesty (Situational Irony)
Even in a time period when modest dress and behavior was expected of women, especially unmarried ones, Griet takes her commitment to modesty more seriously than usual. She is very strict about making sure her hair is entirely covered at all times, and she attempts to avoid any flirtatious behavior with Vermeer. However, ironically, Griet is severe about her modesty because she knows that underneath she is capable of strong feelings of lust and desire. She overcompensates with her external behavior and appearance in order to disguise this internal reality.
Catharina's pregnancies (Dramatic Irony)
Catharina becomes pregnant at frequent intervals in the novel, and it is implied that she does so in order to strengthen her bond with Vermeer. Her many children give her a sense of security and privilege. Ironically, however, the frequent pregnancies actually create distance between Vermeer and Catharina: she is often preoccupied with her condition, and the more children he is responsible for providing for, the more pressure is placed on him. Their large family results in increased economic stress and by the time of Vermeer's death has strained their marriage.
Griet's employment and her brother's employment (Dramatic Irony)
Griet's working class parents dream of a stable life for their children, and in hopes of achieving this goal, as well as providing for their own immediate financial needs, they find employment for both Griet and her brother. However, in an ironic twist, both these jobs introduce more stress and turmoil into the lives of their children. Griet's position as a maid leaves her increasingly discontent with the possibility of a working class future, and also vulnerable to the seduction and manipulation of men such as van Ruijven. Frans's position also makes him envious and unhappy, and leads to him fleeing the city of Delft in disgrace. Employment creates vulnerability and danger more than stability.
