Jaam Tower, sitting on 4,600m2 land plot, adjacent to Shariati Avenue, a centrally historic artery in Tehran running along north-south axis, connecting Tehran’s north Shemiran area, to historical fabric in the city center. The site’s proximity to important highways of Resalat and Hemmat (east-west axis), and Imam Ali and Sayyad (north-south axis), provide fast, easy access and an ideal location in the city. Composed of two volumes: a horizontal commercial platform with a footprint coverage of 80% in two levels, and a vertical office tower with a footprint coverage of ~25% in 25 stories. The complex has 7 underground parking levels, rooftop restaurant, and helipad. Ultimately, making 34stories total. Because of the project’s adjacency to Shariati Park at west, to utilize the roof of the commercial volume as a terrace, and to meet regulations for multi-story construction (pyramidal-outline), a modular system was designed with gradual transformation of the two horizontal/vertical volumes. The simple cubic form of modern office towers was broken into repeatable modules designed with 7.6-meter spans, ideal for different office/commercial spaces and parking. The modules are stacked allowing views of the park on lower levels, and to avoid blocking sunlight and airflow due north. With an unusual transformation, the horizontal platform allows direct access from the park/adjacent sidewalks to the roof-garden (commercial volume), visually merging green space of the park with the project, creating a connection between workspace and landscape; providing consumers views of green landscape, notwithstanding, being in a building in midtown Tehran. In addition to providing suitable solutions to urban and climatic issues, and seamlessly combining the two horizontal/vertical volumes, the project avoids the cliché of modern cuboid towers, replacing it with a penetrating, floating structure. Tehran’s natural north-south slope makes this project visible from different parts of the city, turning it into a distinctive landmark.