For anyone not familiar with the movement for universal design in housing, Introduction to Housing has a chapter that gives a really good overview of how to incorporate UD into the design. It covers each of the design features and explains that they can be factored into moderately sized homes. The chapter addresses each of the classic principles of universal design and how they apply to housing design. A case study illustrates the features. As with many Google Books, many of the pages are freely available, but for the full chapter you will need to contact the authors, Hartje, Ewen and Tremblay or purchase the book.
Introduction to Housing, 2nd edition, is edited by Katrin B. Anacker, Andrew T. Carswell, Sarah D. Kirby, Kenneth R. Tremblay.