I would like to congratulate Nayang Technology University of Singapore for announced the "The Moonshot", a six storey wooden campus, 40,000 sq m GFA（Gross Floor Area), costing S$180 million. The Mass-Engineered Timber building come with a price tag of S$4,500/ sq meter (GFA), double of average construction cost using reinforced concrete, S$925 to S$1,165 (as of 2015 Primary& Secondary school) or S$2,854 to S$3,152 if compare with shopping mall construction cost per square meter as of 2017.
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| Arcadis: Cost Index year 2015. |
Note that I derived S$4,500 from GFA instead of construction area which the two are different though negligible. The cost comparison also didn't take into consideration of the cost index of the period. Broadly speaking, timber building is 1.43 to 4.8 times more costly than building built with reinforced concrete.
So what make the highly efficient Singapore chose to invested in the timber building? What more it is (The Wave) the biggest of its kind in Asia.
I personally very proud of Singapore for pioneering the modern wooden building. It will act as a yardstick for future building to follow suit, at the same time building local industry expertise in wooden building construction. Nonetheless, my support only applicable if the materials is sourced from sustainable manage forest, certified by FSC(Forest Stewardship Council) or equivalent.
What so great about wooden building that still stay reasonable despite its high price tag?
Many would argue that isn't chopping down trees is bad for the environment? It is true if not done properly. Unsustainable logging will cause lost of biodiversity, flooding, landslide, soil erosion, water pollution, lost of carbon sequestration potential of the forest and land (yes, land also sequestrate carbon) and carbon emission. Others negative impact directly affected human are loss of shelter for the indigenous people, loss of livelihood(hunting and small scale agriculture), loss of source of water.
The coming 2020 Olympic games stadium in Japan for example is an unfortunate story for the rainforest. There are at least 4 Japan based NGO protest and pursue the unsustainable source plywood from Sarawak for the Olympic stadium construction. However, government from both country is mute and blind about it as though they never acknowledge any petition and protest on the matter. The disappearance of pristine rainforest and suffering of force eviction of the indigenous settlement is irreversible.
Cash is King here!
Forest that support 1.6 billion people is losing it presence by 30 million acres every year and contributed to 20% of the world carbon emission. Reality is sad, despite FSC is meticulously designed to be environmentally and socially just but its adoption is only up to 10% of the world total working forest. Ten basic principles of FSC reflect the holistic approach of the certification yet there is little motivation for government around the world to make it into by-law. For some egoistic reason or what not, different country may want to create their own certification with their own logo but the bottom line is the content. These certification may mutually recognise each other to have the same effects and gain wider acceptance worldwide since timber industry is very much an international business.
The Ten Principles of FSC are:
The Ten Principles of FSC are:
I belief Singapore, in this context is genuinely wanted to be showcase how wooden building is parallel, if not exceeding, the quality of conventional building construction. In comparison to reinforced concrete, timber has relatively lower weight ratio and able to perform the same fire resistance if properly treated and designed. Unlike reinforced concrete, instead of emitting carbon timber itself is a carbon sink store as much carbon as 50% of its weight. Trees sequestrate carbon dioxide from the atmosphere and use it for body building. Of course, not only the trees in the forest serve as carbon sink the soil on the forest serve the same purpose too thus it is important to manage forest sustainably because wipe up the forest irresponsibility not only lost the potential carbon sequestration from the trees but the carbon sequestration potential of the soil too. Likewise, if manage sustainably, trees is harvest when reach Optimum Rotational Age or Maximum Sustainable Revenue and replanting of trees to ensure regeneration of carbon sequestration potential by aforestation(plant trees at area not a forest)or reforestation while meeting the business objective (profitable).
The YouTube Video reveal how Sustainable managed forest to achieve both economy and environment objectives. Therefore it is almost certain that timber is a better choice as building materials if source from sustainable managed forest. The question that bugging me is whether land on earth is enough to supply for all human needs if would to build with wood? what is the break-even point for forest to cope with demand? is there technology that expedite the production of timber without negative side effects? Human population will hit 9.6 billion in year 2050, the world need answer for the future as much as solving the current problem otherwise we might not even have chance to see the future coming!
Not only wooden building technology improved tremendously to cater for the market needs but conventional building materials such as concrete and steel also evolving to become more environment sensitive. Conventionally, not only cement do not sequestrate carbon but its power intensive production and process that convert calcium carbonate into lime and CO2 as by-product is main reasons for 900kg of CO2 emission for every ton of cement produced. Concrete is made out of Ordinary Portland Cement (OPC), aggregate, sand and water. A 14% cement content emit up to 410kg/m3 of carbon dioxide which is approximately 180kg/tonne for a concrete mix with density of 2,300kg/m3. With the introduce of Fly ash, a by product from coal power plant generator, can replace up to 30% of cement content in the concrete mix effectively reduce carbon dioxide to 290kg/m3. One of the main culprit for the need to fire temperature to 1,500 °C is alite (Ca3SiO5), an ingredient of cement that responsible for early curing (gain strength) of concrete. to reduce the intensity of fossil fuel for that kind of temperature Belite (Ca2SiO4) is an alternative for replacement which can do the same tricks at 1,200 °C however it is not for sure Belite is greener since it take more energy to grind and require more time, like a few days even months to cure, though it yield greater strength than alite. Magnesium can be added to expedite the setting. Other than changes within cement, innovative ways to reduce CO2 is to pump liquid CO2 before the concrete mix thus making it storing carbon into the concrete.
In general, wood is still far superior as a building materials in terms of environmental friendliness, as well as, bring others benefit such as reduction of heat island effects in the urban area and healthier (if not treated with harmful chemical).
It is said that wood is link to spiritual property in many custom belief from the North West Viking to far East Japan and our very Malayunesia (Nusantara- Malay world).
MET(Mas Engineered Timber) is 30% lighter than concrete and has higher strength-to-weight ratio than concrete and steel, allowing The Wave spanning 3 basketball court or 13 badminton court equivalent distance without any internal column. Prefabrication of MET component reduce 25% of manpower and labour cost saving which is a way to improve productivity. Needless to say, it is more sustainable, not only itself act as carbon storage, to as much as 50% of its weight, but the nature of its fabrication allow smaller trees instead of large piece of solid dimension lumber to be used thus matching sustainable managed forestry. Unlike the old days, MET is treated to be more durable from moisture and termite invasion, better fire resistant and thermal insulation. it chars at 0.75mm per minutes instead of burn like what we imagine for BBQ. As for The Wave, it have 50mm allocate for the purpose hence 66.6minutes (~1hr) equivalent of fire resistance before fire meet MET's core.
To learn calculate the Carbon store in the wood, go to http://www.forestry.state.al.us/howMuchCarbonHaveYourTreesStored.aspx
*General assumption is 1 cubic meter of wood equal to 1 ton of CO2 stored thus prevent CO2 from release into atmosphere and cause climate change.
To learn calculate the Carbon store in the wood, go to http://www.forestry.state.al.us/howMuchCarbonHaveYourTreesStored.aspx
*General assumption is 1 cubic meter of wood equal to 1 ton of CO2 stored thus prevent CO2 from release into atmosphere and cause climate change.
MET give an example that sustainable construction materials may be found in primitive materials. Others natural building materials are bamboo (have faster growth rate), earth(adobe and mud,), strawbale, hemp and stone. There are 2 billions people in the world still living in mud houses and there is every reason for it, from thermal comfort, affordability to cultural value. Green materials in the recent decades such as used tire (earthship house), glass bottle, aluminum cannes, plastic, ICF (Insulated Concrete Foam) and others recycled materials is used as building materials. Not only it is not any lesser meeting the functional requirements of building in comparison to the conventional building materials but offer benefits such as divert waste from landfill, reduce GHG emission, and provide very affordable option that contribute to social growth.
Reference:
https://www.bca.gov.sg/keyconstructioninfo/others/intl_constrn_cost_1q17.pdf
https://ic.fsc.org/en/what-is-fsc-certification/principles-criteria/fscs-10-principles
https://ic.fsc.org/file-download.principles-and-criteria-v4.a-1056.pdf:https://ic.fsc.org/file-download.principles-and-criteria-v4.a-1056.pdf:
https://blog.i1machines.com/four-reasons-why-engineered-timber-is-the-building-material-of-the-21st-century-76795ff68e2d
*The blog is solely created and maintaining with my own resource. No obligation, any amount of ex-gratia is very much appreciated.
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