Tweet [I originally wrote this article for the Communitecture blog, where I work as an architect.] What do accessory dwelling units (ADU) have to do with Portland’s state of emergency for housing? Everything. Accessory dwellings are the great compromise between adding density and preserving the single-family fabric that Portlanders have come to love and depend on. They are a great answer to adding housing options in the city without giving up much of the character that makes Portland what it is. [Side Note for Those Not Familiar with ADUs: What the heck is an accessory dwelling unit? It’s what a…