D.C. Mun. Regs. tit. 17, r. 17-3410
For the purposes of this chapter, the term "practice of architecture" means rendering or offering to render services in connection with the design and construction, enlargement, or alteration of a structure or group of structures that have as their principal purpose human occupancy or habitation, as well as the space within and surrounding these structures. These services include planning and providing studies, designs, drawings, specifications, and other technical submissions, and the administration of construction contracts. The practice of architecture does not include the practice of engineering, as defined in D.C. Official Code § 47-2853.131, although an architect may perform engineering work that is incidental to the practice of architecture.
D.C. Mun. Regs. tit. 17, r. 17-3410