Vents are usually required in all sealed crawlspaces, regardless of the presence of a vapor barrier. Unless, of course, you really donít have a crawlspace. Are the floors on this addition wood or concrete?
Also, if you have a crawlspace, can you access it from anywhere else, like the original basement/crawlspace?
Is it truly a brick foundation wall, or cinderblock?
Vents can be purchased at home stores and retrofitted, but you would need to cut appropriately sized holes in the foundation walls.