The use of wood in taller buildings is big news, and now Melanie Sevcenko of the Guardian covers the story of the two towers being built in Portland and New York City. (we covered them here) There are some arguable points (plywood was not invented in Portland) and a few howlers (It is not manufactured by layering panels of 2-ft-by-6-ft lumber, that would be awfully big), but it is a good introduction for the American reader.
But the real fun is in the comments, which repeat, over and over, every misconception that there ever was about building with wood. Some get really angry AND USE UPPER CASE!!!! All of these eye-rollers have been heard before, but I thought it might be a good idea to address them all in one place. Consider it a public service; I read the comments so that you don't have to.
You can’t replace trees as fast as they are being cut down, so the argument that they will grow back is not an acceptable excuse for cutting down the forest. Do your research before you spout off about things you don’t know. Deforestation is one of THE leading contributors to climate change. PERIOD! We need MORE trees on the planet, not fewer!
I’d be interested to see a CO2 ledger of using wood versus concrete. Burning limestone in a kiln to produce concrete obviously is environmentally destructive, but how is wood a long-term alternative?
What about the gassing out of glue used to weld the plywood flats together. What goes into the glue?
What about fire? It says it is fireproof. If CLT uses fireproof chemicals (as ‘fireproof mattresses’ claimed to be in the ‘70s but turned out to be toxic to breathe) will they actually make the walls, ceilings and floors toxic to breathe in? …Like the way the fire issue was skimmed over in two words…..fire death-traps!…We burnt this city. We lost our city of timber and paper. Do the hipsters know history?
What evidence is there that such buildings are healthier?Listen to Amir Shahrokhi of sHop Architects, designer of 475 West 18th St, one of the two buildings discussed in the article. He goes on to talk about fire safety too. Wood makes for a quieter, more comfortable building and thanks to biophilia, makes us feel better. A British Columbia study found:
The presence of visual wood surfaces in a room lowered sympathetic nervous system (SNS) activation. The SNS is responsible for physiological stress responses in humans. This result opens the door to a myriad of stress-related health benefits that the presence of wood may afford in the built environment. The application of wood to promote health indoors is a new tool for practitioners of evidence-based design.
We used to build in wood and stopped!
Funny how the authors of this article, seem to turn a blind eye to the historical precedents that established very clearly, we turned away from timber for high rises, they don’t have to look to far, it’s all there staring them in the face.
I’d like these same people to explain to us , why these days only INTERNAL windows or doors are wood, and all EXTERNAL are aluminium or even steel. …Wood is high maintenance compared to concrete, which is why it’s avoided for cladding buildings, surprised this wasn’t mentioned in the article.
It would be interesting to see if CLT could become a force for renewal in economically depressed regions. Not much in terms of cost comparisons in the article. The construction industry is well aware of the near monopoly that is the global concrete suppliers.
Oregon could become the next hub for cross-laminated timber development and manufacturing due to its rich and diverse timberlands, which rank among the most productive in the world. The combination of high-quality raw materials and value-added manufacturing could revitalize small towns in Oregon’s timber country, creating jobs for sawmill workers and laminators, as well as new business for contractors, suppliers of specialized fittings and connectors and specialized equipment manufacturers.
And finally, a Three-in-one!
There is absolutely nothing wrong with steel or concrete structures. Engineered wood is actually not so great over time and very costly. There’s also a huge problem where most folk think concrete and steel as man made substances and therefore unnatural, non-organic, etc, whereas wood is obviously organic, as the thought process goes. That notion being completely absurd of course, for concrete is wholly from the Earth and quarried from limestone. Steel is nothing more than refined ore, which are essentially rocks. However, engineered wood products contain a plethora of chemicals and treatments that push the limits of human tolerance and safety.
Air emissions from steel manufacturing using the BOF may include PM (ranging from less than 15 kg/t to 30 kg/t of steel). For closed systems, emissions come from the desulfurization step between the blast furnace and the BOF; the particulate matter emissions are about 10 kg/t of steel. In the conventional process without recirculation, wastewaters, including those from cooling operations, are generated at an average rate of 80 cubic meters per metric ton (m3/t) of steel manufactured. Major pollutants present in untreated wastewaters generated from pig iron manufacture include total organic carbon typically 100–200 milligrams per liter, mg/l); total suspended solids (7,000 mg/l, 137 kg/t); dissolved solids; cyanide (15 mg/l); fluoride (1,000 mg/l); chemical oxygen demand, or COD (500 mg/l); and zinc (35 mg/l).The overall impact of steel will be less than this because much is made from recycled steel melted in electric arc furnaces, but it is still a very different thing from wood.And as noted earlier, engineered wood is made with formaldehyde free and solvent free adhesives and is not chemically treated. And as for the "plethora of chemicals and treatments", they do not exist except in the glue, discussed previously, and they are pretty benign compared to the plethora of fireproofing materials needed to protect steel.You can read the rest of the comments here at the Guardian, but they are mostly repetitive.