Curtain wall drainage vent

A curtain wall for a building comprising:

• a frame anchored to the building and including a plurality of frame units, each frame unit including at least one horizontal member defining a lateral slot and at least one vertical member defining a vertical slot;
• infill panels supported by the plurality of frame units and at least partially defining an outer face of the curtain wall;
• at least one drainage vent for venting fluid from inside the curtain wall to outside the curtain wall, the drainage vent defining a fluid flow path extending between a first opening inside the curtain wall and a second opening outside the curtain wall, and further defining opposing first and second sidewall ends, and opposing front and back sidewalls extending between the first and second sidewall ends, wherein a first projection extends into the curtain wall and vertically from the back sidewall to be received within the vertical slot, and opposing second and third projections extend laterally from the opposing first and second sidewall ends, respectively, to be received within the lateral slot on opposing sides of the drainage vent;
• and
• a ball valve arranged within the flow path and including a ball that descends under gravitational force to open the flow path when fluid pressure of wind outside the curtain wall drops, and closes the flow path when the wind increases,
• wherein the second opening is provided in the outer face of the curtain wall, and
• wherein the opposing first and second sidewall ends and the opposing back and front sidewalls collectively define a recess for the collection of water, and the first opening is provided within a base of the recess.