# The Hai 亥 mountain

> A house facing 330° is in the Hai 亥 mountain. Hai covers every bearing from 322.5° up to 337.5°, within the Qian 乾 trigram in the Northwest, element Water. A house facing Hai sits Si 巳 (142.5° – 157.5°) — described as sitting Si, facing Hai. To be sure, measure the facing as an exact degree.

## Facts about the Hai mountain

- Name: Hợi · Hai · 亥
- Degree range: 322.5° – 337.5°
- Center: 330°
- Trigram: Qian 乾 (292.5° – 337.5°)
- Lines (bottom to top): yang, yang, yang
- Direction: Northwest
- Element of the mountain: Water
- Element of the trigram: Metal
- Three Yuan dragon: Human Yuan dragon
- Opposite mountain (sitting): Si 巳 · 142.5° – 157.5°
- Neighbouring mountains: Qian 乾 · Ren 壬
- Birth-year mountain: Birth-year mountain of people born in a Hai (Pig) year, with years counted from the Start of Spring.

## When measuring and setting polarity

The closer a facing is to the 322.5° or 337.5° boundary, the more easily a measuring error pushes it into Qian 乾 or Ren 壬. 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 322.5° – 337.5° sector, seen from the center of the house, belongs to Hai.

The three mountains of Qian 乾: [Xu 戌](https://myhomecheck.ai/learn/24-mountains/tuat) · [Qian 乾](https://myhomecheck.ai/learn/24-mountains/can-tay-bac) · [Hai 亥](https://myhomecheck.ai/learn/24-mountains/hoi)

## Questions about Hai

### Is a house facing 330° a Northwest-facing house?

Yes, but that is not precise enough. The Northwest spans 45° (292.5° – 337.5°) and holds three mountains, Xu, Qian, Hai; a house facing 330° is in Hai. Naming the mountain tells apart houses only a few degrees from each other.

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

It sits Si 巳, 142.5° – 157.5°. Sitting and facing are always exactly 180° apart.

### Whose birth-year mountain is Hai?

It belongs to people born in a Hai (Pig) year, counted from the Start of Spring rather than Lunar New Year. When the main door or an active, heavy item falls exactly in Hai, say precisely whose Hai birth-year mountain it touches.

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