the word housing doesn't have an article before it in english. It's not really a singular thing, more of a concept. A little more abstract.
It is not used in place of house most of the time, for example, people don't say, "I'm going to my housing" or "my housing is that way," it is used for more abstract or conceptual things like, "I need to find housing" (i.e. I need to find somewhere to live!"). Or "that building is for housing supplies." It is also used in the compound noun "housing project" or "housing development." Which refers specifically to a publicly funded development of housing for low-income families.
Hope that helps!