In Xuan Kong Flying Star feng shui, the building period (元运, yuán yùn) is the 20-year “luck cycle” in effect when a structure is completed or first occupied. It sets the natal star framework; annual stars then move on top each year.
Each period lasts about 20 years; nine periods complete a 180-year cycle. This calculator uses the same 1864 anchor as our Flying Star calculator and maps any calendar year to Period 1–9. If your school adjusts the exact switch at Li Chun (solar term, often early February), treat January–early February at a boundary year with your master’s rule.
Major renovations: Some lineages treat a full rebuild or very heavy structural change as a new “birth” year for the chart. This tool only looks at the year you enter.
| Period | Example range (years) | Ruling star (common label) |
|---|---|---|
| 1 一运 | 1864–1883 | 一白贪狼星 |
| 2 二运 | 1884–1903 | 二黑巨门星 |
| 3 三运 | 1904–1923 | 三碧禄存星 |
| 4 四运 | 1924–1943 | 四绿文曲星 |
| 5 五运 | 1944–1963 | 五黄廉贞星 |
| 6 六运 | 1964–1983 | 六白武曲星 |
| 7 七运 | 1984–2003 | 七赤破军星 |
| 8 八运 | 2004–2023 | 八白左辅星 |
| 9 九运 | 2024–2043 | 九紫右弼星 |
After 2043 the pattern repeats: 2044 begins Period 1 of the next cycle, and so on.