# The Yi 乙 mountain

> A house facing 105° is in the Yi 乙 mountain. Yi covers every bearing from 97.5° up to 112.5°, within the Zhen 震 trigram in the East, element Wood. A house facing Yi sits Xin 辛 (277.5° – 292.5°) — described as sitting Xin, facing Yi. To be sure, measure the facing as an exact degree.

## Facts about the Yi mountain

- Name: Ất · Yi · 乙
- Degree range: 97.5° – 112.5°
- Center: 105°
- Trigram: Zhen 震 (67.5° – 112.5°)
- Lines (bottom to top): yang, yin, yin
- Direction: East
- Element of the mountain: Wood
- Element of the trigram: Wood
- Three Yuan dragon: Human Yuan dragon
- Opposite mountain (sitting): Xin 辛 · 277.5° – 292.5°
- Neighbouring mountains: Mao 卯 · Chen 辰
- Birth-year mountain: Not a birth-year mountain — only the 12 Earthly Branch mountains match a birth year.

## When measuring and setting polarity

The closer a facing is to the 97.5° or 112.5° boundary, the more easily a measuring error pushes it into Mao 卯 or Chen 辰. When a reading falls within 1° of either boundary, measure again at several points before setting polarity.

Once polarity is set, every room, door or item lying within the 97.5° – 112.5° sector, seen from the center of the house, belongs to Yi.

The three mountains of Zhen 震: [Jia 甲](https://myhomecheck.ai/learn/24-mountains/giap) · [Mao 卯](https://myhomecheck.ai/learn/24-mountains/mao) · [Yi 乙](https://myhomecheck.ai/learn/24-mountains/at)

## Questions about Yi

### Is a house facing 105° a East-facing house?

Yes, but that is not precise enough. The East spans 45° (67.5° – 112.5°) and holds three mountains, Jia, Mao, Yi; a house facing 105° is in Yi. Naming the mountain tells apart houses only a few degrees from each other.

### What does a house facing Yi sit on?

It sits Xin 辛, 277.5° – 292.5°. Sitting and facing are always exactly 180° apart.

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Original page: https://myhomecheck.ai/learn/24-mountains/at  
Other languages: [Tiếng Việt](https://myhomecheck.ai/vi/tri-thuc/24-son/at/index.md) · [中文](https://myhomecheck.ai/zh/learn/24-mountains/at/index.md)  
Updated: 2026-10-21