A bagua map with directions: the compass version, step by step

Published 2026-08-24

Search for a bagua map and you get two things wearing the same name. One is a three-by-three grid laid over your floor plan with the front door at the bottom. The other is what people usually mean when they add “with directions” or “compass” to the search: eight sectors pinned to north, northeast, east, southeast, south, southwest, west and northwest. The second one is what follows here, and in the compass tradition it is Eight Mansions, or Ba Zhai.

The short version of the difference: the three-door grid rotates with your entrance, and this one does not rotate at all. North is north whichever way your door faces.

Step one: take a bearing, not a guess

Everything here rests on one measurement, so it is worth doing properly. You need the direction the building faces, taken with a compass, in degrees.

A phone compass is usually good enough outdoors and unreliable indoors, where steel in the walls and floor can pull the needle. Stand outside, on the side of the building with the main entrance, facing the same way the building faces, and read the bearing. Take it three times from slightly different spots and see whether the numbers agree.

Two degrees matters here. The 360 degrees are cut into eight sectors of 45, so a reading near a boundary can land the building in a different sector entirely and change every sector’s label. Why that happens, and how to tell whether your reading is near a boundary, is in why two degrees changes your whole chart, and the indoor problem is in how to take a compass bearing indoors.

Step two: turn the bearing into a facing and a sitting

The building has two directions, opposite each other, and both are used:

• Facing — the way the front of the building looks out, the bearing you just took.
• Sitting — the direction directly behind it, 180 degrees away.

The sitting direction is what names the house. A building that faces south sits north, and Eight Mansions takes the name from the sitting trigram, which makes that a Kan house. The whole chart for the building comes from the sitting direction, not the facing one, which is a common place to go wrong — the two are worked through in what is a house gua.

Step three: lay the eight sectors over the plan

Put the center of your floor plan at the middle, and divide the full circle into eight sectors of 45 degrees each, oriented to true compass directions. Each sector covers whatever part of the home falls inside it.

This is the step where the two bagua maps visibly part company. The three-door grid always gives you nine rectangular cells in a fixed arrangement. The compass version gives you eight wedges whose position on the plan depends entirely on which way the building is turned. Two identical houses on opposite sides of a street get identical three-door grids and mirrored compass charts.

An irregular plan raises the same footprint question as the other system — where the outline is not a plain shape, the center moves, and every sector moves with it.

Step four: the part that needs your birth date

Here is the thing that has no equivalent in the three-door system. In Eight Mansions the eight sectors are not labeled the same way for everybody in the house. Each person has a personal number worked out from their birth date and sex, and that number determines which four of the eight directions suit them and which four do not.

So a sector is not simply good or bad. It is favorable for one person and unfavorable for another, and in a household where one person is in the east group and another in the west group, the two sets do not overlap at all — not partly, not at all.

Two things are being read at once, then:

• The house chart, from the sitting direction, which is the same for everyone living there.
• Each person’s chart, from their birth date, which is not.

The four favorable positions carry the names Sheng Chi, Tian Yi, Yan Nian and Fu Wei, and the four unfavorable ones Huo Hai, Wu Gui, Liu Sha and Jue Ming. What each one is traditionally used for is in Sheng Chi, Tian Yi, Yan Nian, Fu Wei.

Why this map answers different questions

Because the compass version knows which way things face, it can say something about a bed, a desk or a stove that the grid version cannot. A bed has a direction the head points; a desk has a direction the sitter faces. Those are directions, so a system built on directions has something to say about them.

The three-door grid has no directions in it, only positions in a plan. It can tell you a bed sits in the cell labeled Family. It cannot tell you which way the bed should point, because nothing in that system points anywhere.

The reverse is also true. The compass version has nothing to say about a cell called Helpful People, because no such thing exists in it.

There is one more thing worth knowing before you use this on your own home: location and direction are separate questions here. A bathroom in a sector that is unfavorable for you is usually treated as a reasonable outcome rather than a problem, because a room you spend little time in is a sensible place for a weak sector. That is not a workaround, it is how the system is meant to be read.

Doing it on your own plan

The bagua map with directions tool takes the bearing and the birth dates, works out the house chart and each person’s chart, and marks the eight sectors on the plan with both readings side by side. If you only want the personal half of it, the Kua number calculator gives the number and the four directions from a birth date, and uses the real start-of-spring date for the year boundary rather than a fixed 4 February.