# Set polarity (立极)

> Setting polarity means finding the centre of a house on its floor plan and placing the compass there, turned to the measured facing degree. Once polarity is set, every room, door and object knows which sector and which mountain it lies in.

- Vietnamese: Lập cực
- English: Set polarity
- Chinese: 立极
- Chinese characters: 立极
- Also called: Lập cực · Setting the compass on a plan

## Explanation

It involves two steps: locating the centre (the pole) of the plan, and rotating the 24-mountain and bagua rings to match the real orientation of the house. For a rectangle, the centre is usually where the diagonals cross; for L-shaped or many-sided homes, it has to be computed from the actual shape.

An error of a few degrees can push the main door or the kitchen into the next mountain, so every feng shui check on a plan starts here.

## How Home Check uses it

Home Check sets polarity by the exact degree, finds the centre from the true shape of the plan, then lays the 24 mountains and the bagua over the drawing to check every position. — [Feng shui check & fix](https://myhomecheck.ai/feng-shui)

## Related terms

- [Center palace](https://myhomecheck.ai/learn/glossary/center-palace): The center palace is the middle square of the nine palaces, around the centre of the house; in the Lo Shu it holds the number 5 and the Earth element.
- [24 Mountains](https://myhomecheck.ai/learn/glossary/twenty-four-mountains): The 24 mountains divide the 360° compass into 24 equal sectors of 15°, each called a mountain.
- [Sitting and facing](https://myhomecheck.ai/learn/glossary/sitting-and-facing): Sitting is the side a house leans its back against; facing is the side it looks out from.
- [Nine palaces (Lo Shu)](https://myhomecheck.ai/learn/glossary/nine-palaces-lo-shu): The nine palaces are a 3×3 grid that divides a plan into eight palaces around a centre palace.

## Questions

### On a multi-storey house, which floor sets the polarity?

Usually the ground floor; the upper floors belong to the same house and share its orientation. In Home Check, if a floor differs from the ground floor, the app asks you to confirm before setting polarity.

### How is setting polarity different from measuring direction?

Measuring gives you one degree. Setting polarity places that degree on the plan, around the true centre, so you know which sector each room is in.

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Original page: https://myhomecheck.ai/learn/glossary/set-polarity  
Other languages: [Tiếng Việt](https://myhomecheck.ai/vi/tri-thuc/thuat-ngu/lap-cuc/index.md) · [中文](https://myhomecheck.ai/zh/learn/glossary/set-polarity/index.md)  
Updated: 2026-10-21