The Secret of Natural Ventilation in Buildings 揭秘建築的自然通風秘訣

大家應該都有過這種經驗吧？夏天在沒有冷氣的空間裡快要被「烤熟」，結果一開窗，突然間一股微風輕輕地溜進來，整個人彷彿被救贖。這其實就是「被動式通風」的小魔法。

It's a blazing hot summer day, and you're stuck in a room with no AC, feeling like you're being slow-roasted. Then you crack open a window, and—bam!—a cool breeze slides in like a hero in a movie. That, my friend, is the magic of passive ventilation.

到底怎樣的建築才是真的『環保』？」說真的，除了什麼太陽能板、回收建材這些顯而易見的做法，其實讓建築「自己會換氣」也是一種超聰明又被低估的永續設計。而這，就是被動式通風的主場。

"What really makes a building eco-friendly?" Honestly, beyond the obvious stuff like solar panels or recycled materials, giving a building the ability to "breathe on its own" is a super smart (and seriously underrated) sustainable design tactic. That’s where passive ventilation comes in.

簡單來說，被動式通風就是讓建築靠自己「呼吸」，完全不需要電風扇或空調幫忙。它的神奇來自於兩種自然力量：一種是風——沒錯，就是風吹來那種風；另一種則是熱空氣的浮力，也就是我們常聽到的「煙囪效應」。熱空氣比較輕，就會往上跑，冷空氣就會補進來。就這麼簡單的原理，但放在建築設計裡，可以玩出很多高招。

In simple terms, passive ventilation means a building breathes without needing fans or AC. It taps into two natural forces: wind—yep, the good old breeze—and the buoyancy of warm air, what we call the "chimney effect." Warm air rises because it’s lighter, cooler air comes in to take its place. It’s basic physics, but in architecture? It’s genius.

我看過一些很聰明的建築設計，像是在建築不同的面向設幾個窗戶，製造穿堂風，風自然就帶著熱氣流動。還有更猛的，像是把建築中間設計成挑高的中庭或通風井，氣流就像搭電梯一樣從下面升上去，把熱氣帶走。有些甚至還加了太陽能煙囪，就是讓太陽幫忙把煙囪內部加熱，這樣上升氣流更強，效果加倍。

I’ve seen some brilliant designs out there. Some buildings place windows on opposite walls to create cross-ventilation—just let the wind do its thing. Others go big, with tall atriums or vertical shafts that act like elevators for hot air, lifting it up and out. Some even add solar chimneys, where the sun heats the chimney and turbocharges that rising airflow.

而且這些設計都不只是「好看」，它們真的超實用。像辛巴威的東門中心，它根本沒裝冷氣，整棟建築就靠自然通風，結果全年室溫都維持得很舒服。還有澳洲RMIT的設計學院，把煙囪和夜間蓄冷樓板搭在一起使用，讓整棟大樓夏天也不用拼命開冷氣。說到這，怎麼能不提我們自己的老智慧？像台灣傳統的三合院，透過中庭和窗戶創造空氣流動，不就是早期的「天然空調」嗎？

And these designs aren't just eye candy—they seriously work. Take the Eastgate Centre in Zimbabwe. No air conditioning. Zero. It’s all passive ventilation, and it stays comfortable year-round. Or look at RMIT’s design school in Australia. They paired chimneys with thermal mass floors that cool at night, so the building barely needs AC in summer. Oh, and let’s not forget our own roots: Taiwan’s traditional three-sided courtyard homes? They’ve been using central courtyards and strategic windows for generations to beat the heat—natural AC before it was cool.

但被動式通風也不是萬能。像是在潮濕又悶熱、連風都不想動的日子裡，光靠自然通風可能還是會悶到懷疑人生。這時候還是得靠點機械通風幫忙。而且設計上也要考慮很多細節，什麼開口大小、位置、朝向，通通都會影響通風效果。

Of course, passive ventilation isn’t magic. On muggy, windless days where even the air is tired, you might still feel like you're stewing. That’s when you need a little mechanical help. And don’t even get me started on the design math—window size, placement, wind direction—it’s an art and a science.

但就算有些限制，被動式通風還是讓人愛不釋手。它省電、省錢、對環境友善，還能讓空氣流動起來，減少病菌和悶氣。最重要的是，它讓我們重新思考建築不只是「避風遮雨」的盒子，而是可以和自然合作、一起呼吸的生命體。

Still, despite the limitations, passive ventilation is a crowd-pleaser. It saves energy, saves money, improves indoor air quality, and gives you that lovely natural breeze that feels way better than a cold blast from a vent. Most importantly, it makes us rethink buildings—not just as boxes that keep the rain out, but as living structures that collaborate with nature.

所以，下次如果你走進一棟清涼通風又沒開冷氣的建築，別懷疑，它可能正在偷偷地「自己呼吸」。而你，也正在享受一種最古老、也最智慧的涼爽方式。

So next time you step into a building that feels fresh and cool, without a single AC hum in the background, don’t be surprised. It’s probably breathing. And you? You’re enjoying one of the oldest, smartest ways to stay cool.

Picture Source：never enough Architecture