# Light well (天井)

> A light well is a vertical void open to the sky that brings light and air into the middle of a house. In narrow, deep tube houses it gives the central rooms daylight and drives a stack-effect breeze.

- Vietnamese: Giếng trời
- English: Light well
- Chinese: 天井
- Chinese characters: 天井
- Also called: Giếng trời · Lightwell · Courtyard void

## Explanation

Architecturally, it usually sits mid-house or by the stair, taking in light and letting heat rise out. In feng shui it is where heaven's energy enters the heart of the home, so it should stay clean and open, with suitable rain protection.

Its size should suit the height of the house: too small gives too little light, too large in a narrow house wastes floor area.

## How Home Check uses it

When you design a house in one sentence, Home Check places a light well where a deep plan needs daylight; you can also ask for one. — [House design](https://myhomecheck.ai/design)

## 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.
- [Hide the wind, gather the qi](https://myhomecheck.ai/learn/glossary/hide-wind-gather-qi): "Hide the wind, gather the qi" — shelter from wind and energy is kept — is the root principle of feng shui.
- [Building coverage ratio](https://myhomecheck.ai/learn/glossary/building-coverage-ratio): Building coverage ratio is the percentage of a plot covered by the building's footprint.

## Questions

### Which homes need a light well?

Tube houses and deep homes whose middle rooms have no window to the outside. Homes open on several sides need one less.

### Does a light well make the house hot?

With proper shading and a vent at the top, it helps hot air rise and escape, keeping the home cooler.

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