This Denver basement renovation transformed an underutilized lower level of a 1920s home into a fully functional accessory dwelling unit. Prenvalley Builders navigated the challenges of aging concrete walls, settled framing, and uneven floors to deliver a code-compliant living space that includes a kitchenette, full bathroom, living area, and private bedroom. Careful coordination and precise execution allowed the team to modernize the structure while preserving the integrity of the existing home. The result is a durable, comfortable lower-level ADU designed to support long-term use and added property value.