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Construction
建筑
The house made of wood
木制房屋
Buildings produce a huge amount of carbon. Using more wood would be greener
建筑物产生大量碳。使用更多木材会更环保
The second little pig was unlucky. He built his house from sticks. It was blown away by a huffing, puffing wolf, which promptly gobbled him up. His brother, by contrast, built a wolf-proof house from bricks. The fairy tale could have been written by a flack for the construction industry, which strongly favours brick, concrete and steel. However, in the real world it would help reduce pollution and slow global warming if more builders copied the wood-loving second pig.
第二只小猪很不走运。他用树枝盖房子。房子很快被一只狼呼哧呼哧地吹走了，然后小猪被吞了。而他的兄弟用砖块建造了一所防狼的房子。这个童话故事可能是建筑业的推销员写的，而建筑业大力支持砖、混凝土和钢铁。然而，在现实世界中，如果更多建筑商模仿热爱木材的第二只猪，将有助于减少污染、减缓全球变暖。
In 2015 world leaders meeting in Paris agreed to move towards zero net greenhouse-gas emissions in the second half of this century. That is a tall order, and the building industry makes it even taller. Cement-making alone produces 6% of the world’s carbon emissions. Steel, half of which goes into buildings, accounts for another 8%. If you factor in all of the energy that goes into lighting, heating and cooling homes and offices, the world’s buildings start to look like a giant environmental problem.
2015年，各国领导人在巴黎举行会议，就本世纪下半叶实现温室气体零排放达成一致。这是一个很高的要求，而建筑行业更难达到。仅水泥制造就产生了全球6%的碳排放。钢铁，其中一半进入建筑，占另外8%。如果把所有用于照明、供暖和制冷的家庭及办公室能源都考虑在内，世界上的建筑似乎有很大的环境问题。
Governments in the rich world are now trying to promote greener behaviour by obliging developers to build new projects to “zero carbon” standards. From January 1st 2019 all new public-sector buildings in the European Union must be built to “nearly zero-energy” standards. All other types of buildings will follow in January 2021. Governments in eight further countries are being lobbied to introduce a similar policy.
发达国家正试图通过强制开发商建造符合“零碳”标准的新项目来促进绿色行为。从2019年1月1日起，欧盟所有新公共建筑必须按照“接近零能耗”的标准建造。所有其他类型的建筑都将于2021年1月建成。另外8个国家也被游说引入类似的政策。
These standards are less green than they seem. Wind turbines and solar panels on top of buildings look good but are much less productive than wind and solar farms. And the standards only count the emissions from running a building, not those belched out when it was made. Those are thought to account for between 30% and 60% of the total over a structure’s lifetime.
这些标准并不像看上去那么环保。建筑顶部的风力涡轮机和太阳能电池板看起来不错，但其生产率远远低于风力和太阳能发电厂。这些标准只计算建筑运行过程中的排放量，而不计算建筑建成时的排放量。而建成过程占建筑总周期的30%到60%。
Buildings can become greener. They can use more recycled steel and can be prefabricated in off-site factories, greatly reducing lorry journeys. But no other building material has environmental credentials as exciting and overlooked as wood.
建筑可以更环保。可以使用更多的可回收钢材，可以在工厂外预制，大量减少卡车行程。但是，其他建筑材料不像木材那样具有明显却被忽视的环保资质。
The energy required to produce a laminated wooden beam is one-sixth of that required for a steel one of comparable strength. As trees take carbon out of the atmosphere when growing, wooden buildings contribute to negative emissions by storing the stuff. When a mature tree is cut down, a new one can be planted to replace it, capturing more carbon. After buildings are demolished, old beams and panels are easy to recycle into new structures. And for retrofitting older buildings to be more energy efficient, wood is a good insulator. A softwood window frame provides nearly 400 times as much insulation as a plain steel one of the same thickness and over a thousand times as much as an aluminium equivalent.
生产一层合木梁所需的能量是同等强度钢梁所需能量的六分之一。树木在生长过程中从大气中吸收碳时，木质建筑通过储存这些物质而产生负排放。一棵成熟的树被砍伐时，可以种植一棵新的树来代替，从而吸收更多的碳。建筑物拆除后，旧梁和旧板很容易再循环成新的结构。为使旧建筑更节能，木材是很好的绝缘体。软木窗框的绝缘性能几乎是同等厚度的普通钢的400倍，是同等厚度的铝的1000倍以上。
A race is on to build the world’s tallest fully wooden skyscraper. But such edifices are still uncommon. Industry fragmentation, vicious competition for contracts and low profit margins mean that most building firms have little money to invest in greener construction methods beyond what regulation dictates.
世界上最高的全木质摩天大楼建造竞赛正在进行。但是这样的建筑仍不多见。行业分裂、合同的恶性竞争和低利润率意味着大多数建筑公司没有资金投资超出监管规定的环保建筑方法。
Governments can help nudge the industry to use more wood, particularly in the public sector—the construction industry’s biggest client. That would help wood-building specialists achieve greater scale and lower costs. Zero-carbon building regulations should be altered to take account of the emissions that are embodied in materials. This would favour wood as well as innovative ways of producing other materials.
政府可以帮助推动木材行业使用更多的木材，特别是公共部门——建筑业最大的客户。这将帮助木材建筑专家做到规模更大、成本更低。零碳建筑法规应加以修改，以考虑到材料本身的排放。这将有利于木材以及生产其他材料的创新方法。
Construction codes could be tweaked to make building with wood easier. Here the direction of travel is wrong. Britain, for instance, is banning the use of timber on the outside of tall buildings after 72 people died in a tower fire in London in 2017. That is a nonsense. Grenfell Tower was covered in aluminium and plastic, not wood. Modern cross-laminated timber panels perform better in fire tests than steel ones do.
建筑规范可以调整，以便更容易使用木材建造。这方面的发展方向是错误的。以英国为例，2017年伦敦一场塔楼火灾造成72人死亡后，英国开始禁止在高层建筑外部使用木材。简直荒唐可笑。格伦费尔塔是用铝和塑料覆盖的，而不是木头。现代交叉叠层木板在防火测试中比钢板性能更好。
Carpentry alone will not bring the environmental cost of the world’s buildings into line. wrong, just before his time.
仅靠木工无法使世界建筑的环境成本一致。但是使用木材不仅仅只是被赞赏，还有更多益处。第二只小猪没有错，只是时代不能理解。
来源：经济学人
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