What are the Eight Mansions?

Feng shui (風水) is mostly about a place, and a place has to be measured. But one strand of it starts with the person instead: 팔택 (八宅, Eight Mansions) takes your birth year and sex and derives a single number, your 명괘 or Kua, which answers to one of the eight trigrams. Kua 1, 3, 4 and 9 make up the East group (동사명); 2, 6, 7 and 8 make up the West group (서사명). Each Kua has four directions that suit it, and each of the four has a job: 생기 (生氣) for what you want to grow, 천의 (天醫) for rest and recovery, 연년 (延年) for people, 복위 (伏位) for steadiness.

Reduce the last two digits of your solar year to a single digit — call it r. A man born before 2000 takes 10 − r, from 2000 onward 9 − r; a woman before 2000 takes r + 5, from 2000 onward r + 6; then reduce again. A result of 5 has no trigram of its own, so it becomes 2 (坤) for a man and 8 (艮) for a woman. East-group Kua draw their four directions from north, south, east and southeast; West-group Kua from west, northwest, northeast and southwest. We checked the formula against eight published anchors — 1963 male → 1, 1972 male → 1, 1980 male → 2, 1985 male → 6, 1994 male → 6, 1994 female → 9, 2000 male → 9, 2004 female → 1 — and all eight agree.

Because “year” is ambiguous here, and the ambiguity can invert your answer. The solar year turns at 立春 in early February, so a birth in January belongs to the previous year — and since the East and West groups alternate, being off by one year can flip your entire set of directions from one half of the compass to the other. The schools genuinely split on this: classical practice uses 立春, while most of the popular Kua tables you will find online use the plain calendar year. Bokki follows 立春, because the rest of our engine does and we would rather be consistent than popular — and when that choice changed your answer, the page tells you it did. One honest edge remains: 立春 falls at an exact hour and we read dates only, so if you were born on 立春 day itself, the hour decides and we cannot tell you which side of it you are on.

The building. Real Eight Mansions work measures a house's sitting-and-facing with a 나경 (luopan) on the spot, and no browser can do that — so Bokki never tells you your home is an East-group or West-group house, and never assigns your rooms. We do not do 현공비성 (Flying Stars), which needs the construction period and a facing measured in degrees. And we publish only the four auspicious directions. The tradition names four inauspicious ones as well; we leave those out on purpose, for the same reason we leave out 方位殺 in Nine Star Ki. A direction is a grain to lean with when something matters — which way to set the desk, which way to face in a conversation that counts — and never a rule you are failing by breaking.

Two places. The Kua page gives you your number, your group and all four directions with what each one is for. The direction page is the practical one — for moving house, or deciding which way the desk or the headboard should point. Your best direction also shows up as one line inside your daily reading, next to your Saju day-master and your Nine Star.

Nine Star Ki — your main star, and where the year begins
Saju — the Four Pillars, and how they are built