Duplex Housing has evolved over the years, but its main beginnings can be traced to making housing affordable for the average American and to be able to buy a home.

During the Great Depression and World War II, the federal support of private suburban housing development (including Duplex Housing) increased greatly. The income tax deduction for mortgage interest (in 1939) was a powerful stimulus. Also, Federal mortgage insurance for G. I. mortgages for veterans after the war and for developers made purchasing a suburban house cheaper than renting an urban apartment. Further more, automobiles made the suburbs more accessible, and federal funds for road building encouraged low-density development.

In addition, Duplex Housing was instrumental during the time of the Civil Rights movement. The Civil Rights Act of 1964, Title VII, prohibits employment discrimination based on race, sex, religion or national origin. Title VI, prohibits public access discrimination, leading to school desegregation. And Title VIII, (as related to Duplex Housing) is the original "federal fair housing law," and it helped provide an opportunity for affordable housing, including Duplex Housing. Later amended in 1988, the Fair Housing Amendment Act of 1988, disabled access required for multi-family housing intended for first occupancy after March 13, 1991.

Today, Duplex Housing had become incredibly common and a main stay in Housing development. It has lasted the test of time and proven itself to be a very successful design.