UCS1001
Critical Thinking
& Communication
Task: Reader
Response
The article, “Will Pure Wooden High-Rise Building Be a Game Changer
for Decarbonisation, Obayashi Corporation’s Challenge” by Clark (2023),
examines how Obayashi Corporation employs wooden construction to create
competitive buildings with a smaller carbon footprint.
The Port Plus Obayashi Yokohama Training Centre uses cross laminated
timber (CLT) and laminated veneer lumber (LVL) as key structural elements. Port
Plus stands out for its implementation of rigid cross joints, which binds
columns and beams using glued in rods (GIR) and a Japanese carpentry technique
known as Nuki (Port Plus, n.d.). Nuki involves sliding a pre-cut section of
lumber into another section. Another feature of Port Plus is the use of “O Mega
Wood” offering fire resistance and earthquake protection comparable to
traditional concrete and steel buildings (Obayashi, n.d.). In an
earthquake-prone country like Japan, wooden construction can provide as a
comparable alternative.
While the article presents a compelling case for wooden construction,
it prompts the question of whether wood harvesting for this purpose truly
achieves meaningful carbon reduction.
The first point to consider is the environmental impact of industrial
scale wood harvesting. Global wood harvests are projected to contribute 3.5 to
4.2 billion metric tons of greenhouse gases to the atmosphere annually in the
foreseeable future, amounting to approximately 10% of recent annual carbon
dioxide emissions (World Resources Institute, 2023). This draws attention to
the crucial function of trees within the forestry ecosystem, where they absorb
carbon dioxide through the process of photosynthesis. When trees are removed,
the disruption extends beyond just carbon dioxide removal. Nutrients flow became
disrupted, affecting surrounding trees, soil and forest bed (Dyck & Mees,
1990). This shows the urgent need to address environmental impact of wood
harvesting on an industrial scale, safeguarding trees and soil health.
The second point to raise is a critical oversight that emerges from
overlooking the inefficiency in wood harvesting. Only a quarter of a harvested
tree is deemed suitable to be used as building materials, with the remaining
three quarters either buried, burnt or left on its own (Peng et al., 2023).
This revelation from a study by Peng and his team prompts the need for a
thorough examination of wood sustainability where a significant portion of wood
harvested remains non-reusable. While the current scale of using wood as a
building material is relatively small, the consequences could be detrimental if
wood were to replace conventional building materials as the norm (Roston,
2023). It is imperative that more comparison studies be conducted in order to
determine whether the use of wood in this manner could still result in lower
carbon emissions overall compared to using concrete and steel.
In one such study by Ramage et al. (2017), they shared two key areas
for future research on wood which are understanding the logistics processes
behind timber trade and formulating appropriate policies, both crucial in
assessing the impact of wood harvesting. Firstly, as stated by the authors, analysing
the carbon footprint across the entire supply chain of timber trade from
logging, processing to transportation and distribution will provide researchers
with a comprehensive understanding of the environmental impact of using wood as
building material. Secondly, this new knowledge can then guide policymakers in
setting international and regional forest strategies to address the challenges
posed by forest harvesting. According to Ramage et al. (2017), effective policy
measures include implementing stringent regulations to control wood usage which
help strike a balance between wood demand and the time needed for trees to grow.
Conducting studies in these areas will facilitate the search for answers to
understand and mitigate the environmental impact of wooden construction.
While the debate about wood’s environmental friendliness persists, it
is undeniably a superior alternative to concrete and steel in terms of carbon
emissions produced. In a study by Buchanan & Honey (1994), they conducted a
comparison of carbon emissions generated from the various building materials.
Wood building materials such as treated timber and glue laminated timber
emitted negative carbon emissions overall as carbon is stored in timber
products whereas, building materials such as structural steel and reinforced
concrete produced 8,117 and 182 kilogram per cubic metric of carbon emissions
respectively. Unlike wood, concrete production involves limestone calcination,
a process which emits carbon dioxide as a byproduct, contributing to high
emission levels (Gustavsson & Sathre, 2006). One positive example
illustrating the viability of transitioning from concrete and steel to wooden
construction can be observed in New Zealand. The increasing trend towards
wooden construction in residential and commercial buildings in New Zealand
could result in 20% reduction in carbon emissions. Furthermore, this shift
could contribute to a 1.8% decrease in New Zealand's total atmospheric carbon
level (Buchanan & Levine, 1999). Hence, such findings present a strong case
for wood as a building material, aligning with global efforts toward
decarbonisation.
In summary, while wood offers significantly lower carbon emission
levels compared to concrete and steel, critical considerations regarding
efficiency, sustainability, and global wood harvesting impact must be addressed
first. Achieving sustainable construction and true carbon reductions
necessitates the need for further comprehensive studies and effective policies.
Reference
Buchanan, A.H., & Honey, B.G. (1994).
Energy and carbon dioxide implications of building construction. Energy and Buildings, 20(3),
205-217. Energy
and carbon dioxide implications of building construction - ScienceDirect
Buchanan, A.H., &
Levine, S.B. (1999). Wood-based building materials and atmospheric
carbon emissions. Environmental Science
& Policy, 2(6), 427-437. Wood-based
building materials and atmospheric carbon emissions - ScienceDirect
Clarke, A. (2023, November 6). Will pure wooden high-rise buildings be a
game changer for decarbonization, obayashi corporation's challenge. Bloomberg. Will
pure wooden skyscrapers be a game changer for decarbonization, Obayashi's
challenge - Bloomberg
Dyck, W.J., & Mees, C.A. (1990).
Nutritional consequences of intensive forest harvesting on site productivity. Biomass, 22 (1-4), 171-186. Nutritional
consequences of intensive forest harvesting on site productivity -
ScienceDirect
Gustavsson, L., & Sathre, R. (2006).
Variability in energy and carbon dioxide balances of wood and concrete building
materials. Building and Environment, 41(7),
940-951. Variability
in energy and carbon dioxide balances of wood and concrete building materials -
ScienceDirect
Obayashi Corporation. (n.d.). Low-cost, long-span fire-resistant wood
construction technology: O･Mega Wood (FR). Low-Cost,
Long-Span Fire-Resistant Wood Construction Technology: O･Mega
Wood (FR) | Appendix | OBAYASHI CHRONICLE 130 English
Port Plus. (n.d.). OY
Project. oyproject.com
Peng, L., Searchinger, T.D., Zionts, J.,
& Waite, R. (2023). The carbon costs of global wood harvests. Nature. The carbon costs of global wood
harvests | Nature
Ramage, M.H., Burridge, H., Busse-Wicher,
M., Fereday, G., Reynolds, T., Shah, D.U., Wu, G., Yu, Li., Fleming, P.,
Densley-Tingley, Danielle., Allwood, J., Dupree, P., Linden, P.F., &
Scherman, Oren. (2017). The wood from
the trees: The use of timber in construction. Renewable and Sustainable Energy Reviews, 68, 333-359. The wood from the trees: The use of
timber in construction - ScienceDirect.
Roston, E. (2023, January 27) Just how
climate-friendly are timber buildings? It's complicated. Portland Press Herald. Just
how climate-friendly are timber buildings? It’s complicated. (pressherald.com)
Searchinger, T.D., Peng, L., Waite, R.,
& Zionts, J. (2023). Harvesting wood has overlooked carbon costs. World Resources Institute. Harvesting
Wood Has Overlooked Carbon Costs | World Resources Institute (wri.org)