觀點：以夯土為基礎的建築工程與回收再生材料進行比較：關於永續建築的省思
Viewpoint: Comparing Earth-Based Construction with Recycled Materials: A Reflection on Sustainable Construction
觀點：以夯土為基礎的建築工程與回收再生材料進行比較：關於永續建築的省思
Original title: Building with earth could transform sustainable construction – here’s how, by Rabia Charef, The Conversation
原始標題：以地球為基礎的建築如何改變永續施工——Rabia Charef，《The Conversation》
We live in an age of profound environmental reckoning, forced to confront the fact that our modern modes of construction are neither infinitely sustainable nor benign in their impact.
我們正處於一個深刻的環境反思時代，被迫面對一個事實，那就是我們現代的建築方式既非無限永續，也非對環境無害。
For decades, we have relied on steel beams, reinforced concrete, and other energy-hungry materials that drain resources from the earth while leaving behind towering heaps of carbon emissions.
數十年來，我們依賴鋼樑、鋼筋混凝土和其他耗能的材料，這些材料消耗地球資源，同時留下高聳的碳排放堆積。
It is in this context that an article from The Conversation (“Building with Earth Could Transform Sustainable Construction—Here’s How”) renews our awareness of a practice that humanity has known for centuries: building with earth itself.
正是在這種背景下，《對話》雜誌的一篇文章（「用土建造可以改變永續建築 — 方法就在這裡」）讓我們重新意識到人類幾個世紀以來就已知曉的一種做法：用土本身來建造。
The authors of this piece extol the virtues of rammed earth, mud bricks, and similar methods that harness local soil, contending that these approaches may cut the environmental cost of construction while providing homes and public spaces that can stand the test of time.
這篇文章的作者讚揚了夯土、土磚和類似方法的優點，這些方法利用當地土壤，認為這些方法可以降低建築的環境成本，同時提供可以經得起時間考驗的住宅和公共空間。
Yet one must note that earthen walls are hardly the only alternative to conventional materials.
然而，必須注意的是，夯土牆絕非傳統材料的唯一替代品。
Across the globe, innovators have turned their sights to recycling or reclaiming waste—be it plastic, timber, or stone scraps—to fashion building blocks that might rival the structural might of concrete or steel while safeguarding the planet’s dwindling resources.
在全球各地，創新者將目光投向回收或再利用廢棄物 —— 無論是塑膠、木材還是石頭碎片 —— 以打造可能與混凝土或鋼鐵的結構強度相媲美的建築材料，同時保護地球日益減少的資源。
In what follows, I aim to compare the article’s chief subject—earth-based construction—to three other recycled or reclaimed materials: (1) plastic waste moulded into bricks, (2) reclaimed wood reconstituted into boards or engineered timber, and (3) stone offcuts turned into tiles or aggregate-based bricks.
在接下來的內容中，我將比較這篇文章的主要主題 —— 夯土建築 —— 與其他三種回收或再利用的材料：(1) 塑膠廢料製成的磚塊，(2) 再生木材製成的板材或工程木材，以及 (3) 石頭碎料製成的磚塊或骨料磚。
My purpose is to explore four key points: the advantages and drawbacks of earth as portrayed in the article; the pros and cons of these other recycled materials; how each might handle the rigours of an earthquake-prone environment; and how their carbon footprints stack up when one takes a more global view.
我的目的是探討四個關鍵點：文章中描述的土建築的優點和缺點；這些其他回收材料的優缺點；每種材料如何在抗震環境中應對嚴峻考驗；以及從全球角度來看，它們的碳足跡如何堆疊。
If we are to reconcile our building needs with the urgent mandate of decarbonisation, we might do well to examine these alternatives through a measured, critical lens that clarifies their promise and pitfalls alike.
如果我們要將我們的建築需求與緊急的脫碳任務相協調，我們不妨以一種衡量、批判的視角來審視這些替代方案，以闡明它們的潛力和陷阱。
1. Advantages and Drawbacks of Earth-Based Construction
1、夯土建築的優點和缺點
Building with earth is older than recorded history. For centuries, people around the world compressed soil into blocks, shaped it into adobe bricks, or packed it tightly between wooden frames to form load-bearing walls.
用夯土建造比有記載的歷史還要古老。幾個世紀以來，世界各地的人們將土壤壓縮成磚塊，塑造成土磚，或將土壤緊緊地塞入木框架中，形成承重牆。
The article from The Conversation points out that this ancestral wisdom, once commonplace, was eventually overshadowed by the rise of steel and concrete.
《對話》雜誌的文章指出，這種曾經普遍存在的祖先智慧最終被鋼鐵和混凝土的興起所掩蓋。
Today, however, many architects and environmentalists believe a revival of earthen construction could significantly reduce our reliance on carbon-intensive building materials.
然而，如今，許多建築師和環保人士認為，夯土建築的復興可以顯著減少我們對碳密集型建築材料的依賴。
Advantages:One cannot overstate the appeal of local abundance.
優點：無法過分強調當地資源豐富的吸引力。
Soil is found nearly everywhere, and with a bit of testing, one can calibrate its composition by adding or subtracting clay, sand, and silt to achieve a workable mixture.
土壤幾乎隨處可見，只要稍微測試一下，就可以通過添加或減少粘土、沙子和淤泥來調整土壤的成分，以獲得可行的混合物。
Because it can be sourced on-site or from a nearby excavation, the raw material requires little transport, cutting out emissions from long-haul trucking.
由於土壤可以在現場或附近的挖掘地點獲得，因此原材料幾乎不需要運輸，減少了長途運輸的排放。
Moreover, earthen walls possess remarkable thermal mass. In a hot climate, they hold off midday heat until well into the evening, at which point they release it gradually.
此外，夯土牆具有顯著的熱容量。在炎熱的氣候中，它們可以阻擋正午的熱量，直到晚上才逐漸釋放。
In colder environments, their insulating properties reduce the need for round-the-clock heating. The indoor climate remains relatively stable, requiring fewer mechanical interventions and lowering overall energy usage.
在較冷的環境中，它們的隔熱性能減少了全天候供暖的需求。室內氣候保持相對穩定，需要更少的機械干預，降低了整體能源消耗。
The article also underscores the breathable nature of earthen walls, which help regulate humidity and ward off mould—an ever-present menace in tightly sealed modern buildings.
這篇文章還強調了土牆的透氣性，這有助於調節濕度並防止黴菌滋生 —— 這在密封嚴密的現代建築中是一個普遍存在的威脅。
Second, the physical and cultural dimension of earthen construction can be a boon to communities that have lost touch with older building traditions.
其次，土建築的物質和文化層面可以成為那些與古老建築傳統失去聯繫的社區的福音。
Certain regions in Africa, Latin America, and the Middle East still feature centuries-old rammed-earth or adobe structures that stand tall despite having endured both time and weather.
非洲、拉丁美洲和中東的某些地區仍然保留著幾個世紀前的夯土或土磚建築，儘管經歷了時間和天氣的考驗，但仍然屹立不倒。
Reviving such practices could restore local identity, preserve ancestral knowledge, and offer a tangible link to place-specific architecture rather than the generic, glassy towers that dominate the skylines of global cities.
復興這些做法可以恢復當地身份，保存祖先的知識，並提供與特定地點的建築的實質聯繫，而不是那些主導全球城市天際線的通用的玻璃塔。
Drawbacks
缺點
Yet the article acknowledges that building with earth also poses challenges in the modern era.
然而，這篇文章承認，在現代，用夯土建造也面臨著挑戰。
The simplicity of soil masks a wealth of complexity: its composition can vary greatly even within the same plot of land, requiring repeated tests for clay and silt content.
土壤的簡單性掩蓋了許多複雜性：即使在同一塊土地上，土壤的成分也可能差異很大，需要對粘土和淤泥含量進行反覆測試。
Builders skilled in concrete or steel often find themselves in unfamiliar territory, needing to relearn the techniques of mixing, tamping, and curing earthen walls.
擅長混凝土或鋼鐵的建築工人常常發現自己身處陌生的領域，需要重新學習混合、夯實和養護夯土牆的技術。
The drying process can be long, subject to humidity and weather patterns. In a construction industry driven by cost and speed, those who propose earthen approaches must convince contractors and developers that this is more than a nostalgic choice.
乾燥過程可能很長，受濕度和天氣模式的影響。在一個由成本和速度驅動的建築行業中，那些提出夯土建築方法的人必須讓承包商和開發商相信，這不僅僅是一個懷舊的選擇。
Another obstacle is the deep-seated prejudice against so-called “mud houses.” In many societies, earthen structures have been dismissed as a symbol of underdevelopment or poverty.
另一個障礙是根深蒂固的對所謂「泥土房」的偏見。在許多社會中，夯土建築被視為落後或貧困的象徵。
Overcoming this bias requires serious public outreach and a series of high-profile success stories—projects that demonstrate how earthen buildings can achieve modern standards of aesthetics, comfort, and structural durability.
克服這種偏見需要嚴肅的公眾宣傳和一系列引人注目的成功案例 —— 證明夯土建築如何能夠達到現代美學、舒適度和結構耐久性的標準的項目。
Without such examples, earthen construction remains a marginal curiosity or an artisan’s niche rather than a mainstream, scalable option.
沒有這些例子，夯土建築仍然是一種邊緣的好奇心或工匠的利基，而不是一種主流的可擴展的選擇。
2. Pros and Cons of Recycled Materials
2、回收材料的優缺點
Alongside earth, builders seeking greener alternatives are exploring a range of recycled or reclaimed materials to reduce the environmental toll of construction.
除了土之外，尋求更環保替代方案的建築師們正在探索各種回收或再利用的材料，以減少建築對環境的影響。
Here we consider three chief examples: plastic-based bricks, reclaimed wood, and recycled stone waste.
這裡我們考慮三個主要的例子：塑膠磚、再生木材和回收石材廢料。
Recycled Plastic Bricks (“Eco-Bricks”)
回收塑膠磚（「環保磚」）
Plastic is ubiquitous, and it is no secret that millions of tonnes of discarded bottles and packaging end up in landfills or oceans each year.
塑膠無處不在，眾所周知，每年有數百萬噸廢棄的瓶子和包裝最終被送往垃圾填埋場或海洋。
Some innovators have proposed compressing or melting plastic waste into sturdy blocks that can replace or supplement conventional masonry.
一些創新者提議將塑膠廢料壓縮或熔化成堅固的磚塊，可以取代或補充傳統的砌築材料。
These so-called eco-bricks boast a lighter weight than concrete and can reduce pollution by diverting plastic from waste streams.
這些所謂的環保磚比混凝土輕，並且可以通過將塑膠從廢物流中轉移來減少污染。
Advantages
優點
Eco-bricks can be fabricated at relatively low cost if an appropriate recycling infrastructure is in place.
如果建立了適當的回收基礎設施，環保磚的製造成本相對較低。
Because they are lightweight, builders might save on transportation costs.
由於它們重量輕，建築商可能會節省運輸成本。
Their insulation properties vary depending on the type of plastic, but many plastic-based bricks can help keep indoor temperatures stable, especially if paired with other insulating elements.
它們的隔熱性能因塑膠種類而異，但許多塑膠磚可以幫助保持室內溫度穩定，特別是如果與其他隔熱元件搭配使用。
Above all, plastic bricks offer the moral satisfaction of reusing a troublesome waste product, thereby relieving pressure on landfill space.
最重要的是，塑膠磚提供了重新利用麻煩廢品的道德滿足感，從而減輕了垃圾填埋場的壓力。
Drawbacks:
缺點
Despite their attractions, recycled plastic bricks still face significant hurdles.
儘管有這些吸引力，回收塑膠磚仍然面臨著重大障礙。
If exposed to excessive heat or flame, plastic can melt, warp, or release toxic fumes, raising questions about fire safety.
如果暴露在過高的熱量或火焰中，塑膠可能會熔化、變形或釋放有毒煙霧，引發關於防火安全的疑問。
The structural integrity of plastic-based blocks is also a concern, especially under heavy loads or shear forces. Many prototypes rely on binding agents or other materials to improve rigidity, which might increase costs or complicate production.
塑膠磚的結構完整性也令人擔憂，特別是在重載或剪切力作用下。許多原型依賴於粘合劑或其他材料來提高剛性，這可能會增加成本或使生產複雜化。
Furthermore, critics worry that if these bricks degrade or break, microplastics could re-enter the environment.
此外，批評者擔心，如果這些磚塊降解或破裂，微塑膠可能會重新進入環境。
While a promising idea, plastic-brick construction demands careful oversight and rigorous performance tests before it can become a widely accepted norm.
雖然是一個很有希望的想法，但塑膠磚建築需要仔細監督和嚴格的性能測試，才能成為廣泛接受的標準。
Reclaimed Wood Products
再生木材產品
Timber, in some shape or form, has been a mainstay of human building since time immemorial.
木材，以某種形式，自古以來一直是人類建築的支柱。
In recent years, “green” construction practices have placed renewed emphasis on reclaiming wood from demolition sites, shipping pallets, or manufacturing offcuts.
近年來，「綠色」建築實務強調從拆除現場、運輸托盤或製造廢料中回收木材。
This timber can be planed or milled into boards, or even pressed into engineered wood products such as cross-laminated timber (CLT).
這些木材可以刨成板材，甚至壓製成工程木材產品，例如交叉層壓木材 (CLT)。
Advantages
優點
Reclaimed wood circumvents the need to harvest new trees, thereby conserving natural forests that store carbon and support biodiversity.
再生木材避免了砍伐新樹木的必要性，從而保護了儲存碳和支持生物多樣性的自然森林。
Reusing the timber also means that the carbon locked into that wood remains sequestered, instead of being released through decomposition or incineration.
重複使用木材也意味著鎖定在木材中的碳仍然被封存，而不是通過分解或焚燒釋放。
Wood-based structures typically have a warm, natural ambience that appeals to many homeowners and architects.
木結構通常具有溫暖、自然的氛圍，吸引許多房主和建築師。
In certain seismic zones, well-constructed wooden frames can bend without fracturing, offering a form of built-in resilience to shaking.
在某些地震帶，建造良好的木框架可以在不折斷的情況下彎曲，提供一種抗震的內在韌性。
Drawbacks
缺點
One must remember, however, that not all reclaimed wood is created equal. Boards salvaged from a demolition site may bear hidden nails, cracks, or rot.
然而，必須記住，並非所有再生木材都是一樣的。從拆除現場回收的板材可能存在隱藏的釘子、裂縫或腐爛。
Chemical contamination—such as old lead-based paints or industrial residues—can pose health risks if not treated correctly.
如果處理不當，化學污染 —— 例如舊的鉛基塗料或工業殘留物 —— 會對健康造成危害。
Quality control thus becomes a significant undertaking, requiring dedicated sorting, testing, and certification.
因此，品質控制成為一項重要的工作，需要專門的分類、測試和認證。
Engineered timber solutions like CLT may be challenging to produce at scale from purely reclaimed sources, given the tight tolerances needed to glue multiple layers.
由於粘合多層所需的公差很嚴格，因此從純粹的再生來源大規模生產像 CLT 這樣的工程木材解決方案可能具有挑戰性。
Furthermore, wood is less dense than earthen or concrete walls, so while it can excel in seismic design, it may not store and release heat in quite the same way.
此外，木材的密度低於土牆或混凝土牆，因此雖然它在抗震設計中表現出色，但它可能無法以相同的方式儲存和釋放熱量。
Builders in very cold or very hot regions often combine wood frames with additional insulation to achieve comfortable indoor temperatures.
在非常寒冷或非常炎熱的地區，建築商通常將木框架與額外的隔熱材料結合起來，以實現舒適的室內溫度。
Stone Waste Recycling
石材廢料回收
Quarrying stone for countertops, monuments, or construction blocks produces significant offcuts and debris.
開採石材用於製作檯面、紀念碑或建築塊會產生大量的廢料和碎屑。
Rather than sending these fragments to landfills, some recyclers now grind them into aggregates or fashion them into decorative tiles, bricks, or panels.
一些回收商現在將這些碎片研磨成骨料，或將它們製成裝飾性的瓷磚、磚塊或面板，而不是將它們送往垃圾填埋場。
Advantages
優點
Stone waste repurposed in this manner harnesses a material prized for its durability and aesthetic appeal.
以這種方式重新利用石材廢料可以利用一種以其耐用性和美觀性而聞名的材料。
Crushed stone can serve as aggregate for new concrete, reducing the need for fresh gravel. Likewise, tiles or veneers made from recycled stone can impart an upscale look without further mining virgin rock.
碎石可以用作新混凝土的骨料，減少對新鮮礫石的需求。同樣，由回收石材製成的瓷磚或飾面可以賦予高檔的外觀，而無需進一步開採原始岩石。
Since many forms of stone—granite, marble, limestone—are dense and wear-resistant, they can stand up well to heavy traffic, extreme temperatures, and other stressors.
由於許多石材 —— 花崗岩、大理石、石灰石 —— 密度大且耐磨，因此它們可以很好地承受人流量大、極端溫度和其他壓力。
Recycled stone also helps cut down on the energy costs tied to quarrying, shipping, and processing newly extracted material.
回收石材還有助於降低與開採、運輸和加工新開採的材料相關的能源成本。
Drawbacks
缺點
Stone is heavy, so transporting it—even in recycled form—can be energy-intensive if the distance between demolition or quarry sites and the recycling facility is great.
石材很重，因此運輸它 —— 即使是回收的形式 —— 如果拆除或採石場與回收設施之間的距離很遠，也可能很耗能。
Sorting different types of stone may require specialised machinery, raising up-front processing costs. Inconsistency in colour or composition can complicate the creation of uniform tiles, bricks, or aggregates.
對不同類型的石材進行分類可能需要專門的機器，從而提高前期加工成本。顏色或成分的不一致性會使製造均勻的瓷磚、磚塊或骨料變得複雜。
While these challenges are not insurmountable, they do highlight that stone recycling hinges on local infrastructure and a reliable supply chain—conditions that may not be equally present everywhere.
雖然這些挑戰並非不可克服，但它們確實表明石材回收依賴於當地基礎設施和可靠的供應鏈 —— 這些條件可能並非在所有地方都同樣存在。
3. Feasibility in Earthquake-Prone Regions
3、在地震易發地區的可行性
No overview of building materials would be complete without considering seismic resilience.
沒有考慮抗震能力，任何關於建築材料的概述都不會完整。
Earthquakes are sudden, brutal tests of a structure’s ability to bend, absorb shocks, and remain standing.
地震是對建築物彎曲、吸收衝擊和保持直立能力的突然、殘酷的考驗。
Conventional reinforced concrete—despite its high carbon footprint—still dominates in many earthquake zones because engineers and regulators have decades of experience quantifying its strength and ductility.
傳統的鋼筋混凝土 —— 儘管其碳足跡很高 —— 仍然在許多地震帶佔主導地位，因為工程師和監管機構在量化其強度和延展性方面擁有數十年的經驗。
But how do earthen walls, plastic-based bricks, reclaimed wood, and recycled stone products compare?
但是，土牆、塑膠磚、再生木材和回收石材產品相比如何呢？
Earthen Construction in Quake Zones
地震帶的土建築
Because traditional earthen walls (rammed earth, adobe) can be brittle, they risk cracking under lateral seismic loads. However, modern techniques have emerged to mitigate this issue.
由於傳統的土牆（夯土、土磚）可能很脆，因此它們在橫向地震荷載作用下有破裂的風險。然而，現代技術已經出現來減輕這個問題。
Builders can stabilise the soil with small amounts of cement or lime, embed steel rods, or install wire mesh along critical points.
建築商可以用少量水泥或石灰來穩定土壤，嵌入鋼筋，或在關鍵部位安裝鐵絲網。
In many parts of the world, earthen structures retrofitted or constructed with these reinforcements have survived moderate quakes.
在世界許多地方，用這些加固措施改造或建造的土建築已經經受住了中等地震的考驗。
The Conversation article hints at ongoing research to codify these reinforcements in building regulations, so that inspectors and developers have clear guidelines.
《對話》雜誌的文章暗示正在進行的研究，旨在將這些加固措施編入建築法規，以便檢查員和開發商有明確的指導方針。
While an earthen structure may never match the brute force resilience of high-grade reinforced concrete, with proper design it can offer a safe and sustainable alternative for low-rise or mid-rise buildings in areas with moderate seismic risk.
雖然夯土建築可能永遠無法與高品質鋼筋混凝土的抗震能力相提並論，但經過適當的設計，它可以為地震風險中等的地區的低層或中層建築提供安全且可持續的替代方案。
Plastic Bricks Under Seismic Stress
塑膠磚在地震壓力下的表現
Advocates of plastic-based bricks argue that their lighter weight might be beneficial in certain seismic scenarios.
塑膠磚的支持者認為，它們的重量較輕，在某些地震情況下可能是有益的。
A lighter wall exerts less force on a building’s foundation and may sway more in step with ground motion, rather than snapping like a rigid block. Still, tests remain limited.
較輕的牆壁對建築物的基礎施加的力較小，並且可能隨著地面運動而更多地搖擺，而不是像堅硬的塊體一樣斷裂。然而，測試仍然有限。
One worry is the deformation of plastic over time, particularly in hot climates, which could undermine structural integrity. Another issue is how well plastic-based bricks can be anchored to each other and to supporting beams or columns.
一個擔憂是塑膠隨著時間的推移而變形，特別是在炎熱的氣候中，這可能會損害結構完整性。另一個問題是塑膠磚如何很好地相互固定以及固定到支撐梁或柱子上。
Without thorough mechanical connections, a quake could cause walls to buckle or separate.
如果沒有徹底的機械連接，地震可能會導致牆壁彎曲或分離。
Until plastic bricks are systematically tested in seismic labs and standardised through building codes, many engineers will be hesitant to employ them for primary load-bearing walls in high-risk zones.
在塑膠磚在抗震實驗室中進行系統測試並通過建築法規標準化之前，許多工程師將猶豫不決，不願意將它們用於高風險地區的主承重牆。
Reclaimed Wood in Earthquake Regions
地震地區的再生木材
Wooden frames, especially when braced with metal connectors, have a proven track record in earthquake-prone areas.
木框架，特別是在用金屬連接件加固的情況下，在易發地震的地區具有良好的記錄。
Traditional Japanese timber architecture, for example, has survived countless tremors because wooden joints allow for controlled movement, distributing stress rather than shattering.
例如，傳統的日本木結構建築已經經受了無數次地震的考驗，因為木質接頭允許受控的運動，將應力分散而不是破碎。
Reclaimed wood can share in these virtues, provided it is structurally sound and meticulously inspected.
再生木材可以分享這些優點，前提是它結構完好且經過仔細檢查。
However, if the boards carry hidden weaknesses or if there is inconsistency in the quality of salvaged timber, building a tall or complex structure might introduce risks.
然而，如果板材存在隱藏的缺陷，或者回收木材的品質不一致，建造高層或複雜的建築可能會帶來風險。
Designers who use reclaimed wood typically supplement it with engineered beams or cross-laminated timber panels, which can be easier to calibrate.
使用再生木材的設計師通常會用工程梁或交叉層壓木材面板來補充它，這些面板更容易校準。
In smaller-scale projects, like single-family homes or low-rise buildings, reclaimed wood can be ideal if accompanied by proper checks and reinforcements.
在較小的項目中，例如單戶住宅或低層建築，如果伴隨著適當的檢查和加固，再生木材可能是理想的選擇。
Recycled Stone and Earthquake Performance
回收石材和抗震性能
Stone, in either natural or recycled form, tends to be more rigid and less flexible than wood. As such, stone-based structures risk cracking unless carefully engineered with steel reinforcement or other bracing systems.
石材，無論是天然的還是回收的，往往比木材更堅硬，也更不易彎曲。因此，石材建築有破裂的風險，除非用鋼筋或其他支撐系統精心設計。
Recycled stone used as aggregate in concrete or mortar can help produce robust masonry, but the key lies in ensuring enough ductility within the overall structural design.
用作混凝土或砂漿中骨料的回收石材可以幫助生產堅固的砌體，但關鍵在於確保整個結構設計中有足夠的延展性。
If recycled stone is shaped into large tiles or bricks, each piece must be properly joined with suitable mortar or adhesives that accommodate lateral shifts.
如果回收石材被製成大型瓷磚或磚塊，則每個部件必須用適當的砂漿或粘合劑正確連接，以適應橫向位移。
While stone-based construction can excel in static load-bearing contexts, engineers must pay extra attention to seismic design to avoid sudden fracture.
雖然石材建築在靜態承重環境中表現出色，但工程師必須格外注意抗震設計，以避免突然斷裂。
Thus, recycled stone is best used in tandem with rebar, metal ties, or flexible frameworks, unless local seismic risk is minimal.
因此，除非當地地震風險很小，否則最好將回收石材與鋼筋、金屬連接件或柔性框架一起使用。
4. Comparison of Overall Carbon Footprints:
全面碳足跡的比較
Finally, we should weigh the environmental credentials of each material in terms of carbon emissions across its life cycle. Construction’s carbon footprint arises from the extraction, processing, and transportation of raw materials, as well as the building’s operational energy use over decades.
最後，我們應該從生命週期的碳排放角度，來評估每種建材的環保資格。建築物的碳足跡來自於原材料的開採、加工和運輸，以及建築物數十年來的營運能源使用。
End-of-life scenarios—demolition, reuse, or recycling—also factor into the equation.
生命週期結束的場景，例如拆除、再利用或回收，也都納入考量。
Earthen Construction and Carbon:
夯土地建築與碳排
Because local soil requires no extensive manufacturing, nor does it demand long-distance shipping, earthen buildings often feature impressively low embodied carbon.
由於當地土壤不需要大規模的製造，也不需要長途運輸，因此夯土建築通常具有令人印象深刻的低隱含碳排放。
Stabilising the soil with small amounts of cement or lime does introduce some emissions, but nowhere near the scale of a fully cement-based construction.
用少量水泥或石灰穩定土壤確實會產生一些排放，但遠不及全水泥建築的規模。
As the article highlights, earthen walls also moderate indoor temperatures, slashing heating and cooling costs across the building’s lifetime.
正如文章所強調的，夯土牆也能調節室內溫度，在建築物的整個生命週期內大幅降低供暖和製冷成本。
This synergy of low embodied carbon and reduced operational energy is what makes earthen construction an attractive choice in the quest to minimise environmental harm.
這種低隱含碳排放和減少營運能源的協同作用，使夯土建築成為在追求最小化環境危害的過程中，具有吸引力的選擇。
The caveat is that earthen buildings must be well-designed to handle moisture, which can compromise structural integrity and necessitate frequent repairs.
需要注意的是，夯土建築必須設計良好，才能應對濕氣，濕氣會損害結構完整性，並需要經常維修。
Still, when properly maintained, an earthen structure’s carbon footprint remains markedly smaller than that of a typical concrete edifice of comparable size.
然而，如果維護得當，土建築的碳足跡仍然顯著小於同等規模的典型混凝土建築。
Plastic Bricks and Their Carbon Accounting:
塑料磚及其碳排放計算
Turning plastic waste into bricks can deliver a mixed verdict on carbon. On one hand, it reclaims a persistent pollutant that would otherwise idle in a landfill or degrade into microplastics in the sea.
將塑膠廢棄物變成磚塊，可以對碳排放產生好壞參半的結果。一方面，它回收了持久性的污染物，否則這些污染物會在垃圾填埋場中閒置，或在海中分解成微塑膠。
On the other, the process of collecting, cleaning, shredding, and moulding plastic demands energy, which may or may not come from fossil-fuel-based grids.
另一方面，收集、清潔、粉碎和塑形塑膠的過程需要能量，而這些能量可能來自化石燃料發電網，也可能不來自化石燃料發電網。
If a region’s electricity is heavily reliant on coal, for instance, the carbon footprint of melting plastic remains significant.
例如，如果一個地區的電力嚴重依賴煤炭，那麼熔化塑膠的碳足跡仍然很大。
Plastic bricks also lack the thermal mass to moderate indoor temperatures on their own, so additional insulation or climate control may be necessary, raising operational energy use.
塑料磚也沒有足夠的熱質量來自行調節室內溫度，因此可能需要額外的隔熱或氣候控制，從而提高營運能源使用量。
Advocates counter that if the plastic bricks are used intelligently—incorporating layers of air pockets, for example—they might improve insulation and thus reduce heating or cooling needs.
倡導者反駁說，如果塑膠磚使用得當 —— 例如，加入多層氣穴 —— 它們可能會改善隔熱性能，從而減少供暖或製冷需求。
But the net result depends on local factors: the source of plastic waste, the energy mix used in the recycling process, and the building’s final design.
但最終結果取決於當地因素：塑膠廢棄物的來源、回收過程使用的能源組合以及建築物的最終設計。
Reclaimed Wood’s Climate Benefits:
回收木材的氣候效益
Among the recycled options, reclaimed wood is notable for storing carbon that trees absorbed during growth. By reusing the wood, one defers its eventual decomposition or burning, both of which would send carbon back into the atmosphere.
在回收選項中，回收木材值得注意的是，它儲存了樹木在生長過程中吸收的碳。通過重複使用木材，可以延遲其最終分解或燃燒，這兩種過程都會將碳釋放到大氣中。
Sourcing, sorting, and processing salvaged wood does take energy, but nowhere near as much as manufacturing concrete or steel from scratch.
採購、分類和加工回收木材確實需要能量，但遠不及從頭製造混凝土或鋼材所需的能量。
Moreover, if properly maintained, wooden structures can last for decades, even centuries, further prolonging that carbon sequestration. Operationally, however, wood does not offer the same large thermal mass that earthen walls do.
此外，如果維護得當，木結構可以持續數十年，甚至數百年，進一步延長碳封存。然而，在營運方面，木材不提供與土牆相同的熱質量。
To maintain comfortable indoor temperatures in extreme climates, one might need insulation or supplemental materials.
為了在極端氣候下維持舒適的室內溫度，可能需要隔熱或補充材料。
Still, from the vantage point of embodied carbon—especially if the wood is sourced locally—reclaimed timber emerges as one of the more planet-friendly choices.
然而，從隱含碳的角度來看 —— 特別是如果木材來自當地 —— 回收木材成為更環保的選擇之一。
Recycled Stone and Carbon Footprints:
回收石材與碳足跡
Stone, whether newly quarried or recycled, is not associated with the high CO₂ releases we see in cement production or steel smelting.
石材，無論是新開採的還是回收的，都不會像水泥生產或鋼鐵冶煉那樣產生高量的二氧化碳排放。
That said, quarrying and cutting stone can be energy-intensive, and heavy stone blocks require considerable fuel for transportation. Repurposing stone offcuts reduces the demand for fresh extraction, diminishing the environmental toll.
話雖如此，開採和切割石材可能需要大量能量，而沉重的石塊需要大量的燃料運輸。將石材邊角料再利用，可以減少新開採的需求，進而降低對環境造成的負擔。
Moreover, stone is durable and often outlasts other materials, making it a sound choice for floors, cladding, or architectural features that might otherwise be replaced or renovated more frequently.
此外，石材耐用，而且通常比其他材料更持久，這使得它成為地板、覆層或建築特色的理想選擇，否則這些特色可能會更頻繁地被更換或翻新。
If the recycling facility and building site lie within reasonable distance of each other, the overall carbon footprint shrinks appreciably.
如果回收設施和建築工地距離彼此合理，則總體碳足跡會顯著減少。
On the operational side, stone’s thermal performance depends on how and where it is used; stone floors can store heat in sunny climates, while thick stone walls can modulate temperature in ways akin to earthen construction—though perhaps not as effectively unless carefully designed.
在實際使用層面上，石材的熱能表現取決於它的安裝方式與環境，如在陽光充足的氣候下，石質地板可蓄熱；而厚實的石牆也能像土牆那樣調節溫度，儘管若未妥善設計，效果可能不及土造建築。
Still, the net climate benefit of recycled stone rests on a well-organised supply chain and a building design that takes advantage of its longevity.
總體而言，回收石材對氣候的正面效益，仍仰賴完善的供應鏈協作，以及能充分利用其耐久特性的建築設計。
Concluding Reflections:
結論省思
No single material alone can solve the monumental challenge of lowering carbon emissions and conserving resources in construction. The Conversation article shows that earthen methods—once dismissed as old-fashioned—can coexist with modern, eco-friendly innovations.
沒有哪一種材料能單獨解決降低碳排放和節約建築資源的巨大挑戰。《對話》的文章表明，曾經被認為過時的土法建築，可以與現代的環保創新共存。
If reinforced and well-maintained, earthen walls offer resilience, comfort, and reduced embodied carbon compared to standard steel-and-concrete systems. Yet other reclaimed or recycled materials merit attention.
只要加強防護並妥善維護，夯土牆與標準的鋼筋混凝土系統相比，不僅韌性高、舒適度佳，還具備更低的隱含碳排放量。然而，其他回收或再利用的材料也值得關注。
Plastic-based bricks tackle our plastic glut but face concerns about fire safety, structural integrity, and microplastics. Reclaimed wood can sequester carbon and draw on age-old craftsmanship, though supply and quality checks complicate large-scale use.
以塑料為基底的磚塊雖能解決過量塑料問題，但卻衍生消防安全、結構穩定度與微塑料污染的隱憂。回收木材能固碳並結合傳統工藝，但其供應量和品質審核在大規模應用上相對複雜。
Recycled stone, similarly, spares fresh quarrying but can be heavy to transport and process.
回收石材亦能減少新開採作業，惟在運輸與加工方面可能因其重量而造成負擔。
In earthquake zones, each approach requires thoughtful design: earthen walls need stabilisation, plastic bricks benefit from framing, wood must be verified sound, and stone should be supported by ductile reinforcements.
在地震區，每種方法都需要謹慎的設計：夯土牆需要加固，塑膠磚需要框架，木材需要驗證其堅固性，而石材需要柔性加固支撐。
None uniformly surpass concrete, but each broadens our material options, responding to local climate, resources, and cultural norms rather than following a single blueprint. Carbon footprints also vary.
雖然尚無任何選項能全面超越混凝土，但這些材料都能擴充我們的建材選擇，並因應當地氣候、資源與文化，而非一體適用於所有情境。同時，各種材料的碳足跡也不盡相同。
Earth-based building excels with its low embodied carbon and inherent temperature regulation; plastic bricks divert waste but may consume fossil-fuel-based energy in production; reclaimed wood locks in carbon from earlier growth cycles, although scaling up remains tricky; and recycled stone endures for decades but involves shipping heavy loads.
夯土建築在低隱含碳與溫度調節上展現優勢；塑料磚可回收廢棄物，但製程可能仰賴化石燃料；回收木材能鎖住早先生長階段的碳，惟大量供應仍具挑戰；回收石材耐用度高，但搬運時相對笨重。
Which route yields the best climate outcome depends on regional energy sources and construction traditions.
至於哪條路徑能帶來最佳的氣候效益，則取決於當地的能源來源與建造傳統。
Still, one shared principle emerges: resource circularity. Earth can be reused on-site; plastics are granted a second life; timber is salvaged rather than felled anew; and stone scraps are repurposed instead of discarded.
然而，它們均呼應一項共同原則：資源循環再利用。土壤可就地使用、塑料獲得第二次生命、木材得以再度回收而非重新砍伐、石材邊角料也能迴避被丟棄的命運。
Realising this vision demands policy changes, robust training, and public acceptance. Demonstration projects and research can dispel myths and showcase viable, appealing structures.
實現這樣的願景，需仰賴政策改革、完善的技能培訓，以及社會大眾的接受度。示範項目和研究可以消除神話，並展示可行且吸引人的結構。
Amid the climate crisis, earth-based methods set a powerful example of blending old wisdom with modern insight.
在氣候危機中，以地球為基礎的方法為將古老智慧與現代洞察力融合在一起樹立了強有力的榜樣。
In time, we may see hybrid designs—earthen cores paired with reclaimed wood or recycled stone cladding—and skylines shaped by local needs and inventiveness.
隨著時間的推移，我們可能會看到混合設計 —— 夯土製核心與回收木材或回收石材覆層相結合 —— 以及由當地需求和創造力塑造的天際線。
Each solution has drawbacks, but only by recognising and refining these alternatives can we achieve a more sustainable and enduring building culture.
雖然各種方案都不盡完美，唯有正視並改良這些選擇，才能推進更永續且更能歷久不衰的建築文化。
