Resumen
The construction of flats is one of the steps toward fulfilling the need for housing in Jakarta and other big cities in Indonesia. This study investigated the thermal problems that focus on air movement in residential units of flats due to window dimensions that cannot accommodate the air velocity that surrounds the buildings because of monotonous window dimensions and the high elevation of the residential units. The position of the interest of this research is on the search for window dimensions that allow comfortable air movement in the residential unit. Based on these problems and interest, the pertinent issue is the design of window dimensions within the facades of the buildings according to the actual air velocity and the elevation of the residential units. The selected object of study was the Jatinegara Barat flats, a block of high-rise flats located in the middle of East Jakarta, Indonesia, which is adjacent to the river. We used a quantitative deductive methodology for the problem analysis via mathematical and simulation methods that use the Ansys R1 2020 software. The final results showed that the relationships between window dimensions, air velocity, and the elevation of residential units can be mapped horizontally and vertically by paying attention to the locations of the window openings with respect to the wind direction and building layout. The horizontal and vertical maps showed repetition of the window dimensions every four floors, with the four floors in the center of the building (read vertically) having window dimensions one-quarter smaller than the four floors above and four floors below.