For the people saying "fire!"...<p>Wood went out of fashion because of urban fires, resource (natural forest) depletion and long term maintenance (rot, termites..) issues.<p>Modern engineered timber (according to proponents) solves these problems. It's engineered from renewable crops of fast growing timber, is resistant to fire and pests... Proponents claim it is now suitable for skyscrapers but certainly for 5-15 story urban residential buildings.<p>Imo.. what is missing are clear advantages, a reason to bother. I don't think there's much cost advantage at this point. Weight savings.. maybe there are some applications where this is important. Generally, it's a bit of a solution searching for a problem.
> A recent advance in wood technology should interest the neighborhood’s developers: Teng Li, a University of Maryland mechanical engineer, created with his colleagues wood that’s as “strong as steel, but six times lighter,” he said. Liangbing Hu, Li’s co-author on the study, added, “This kind of wood could be used in cars, airplanes, buildings—any application where steel is used.” Making it is just a two-step process. The scientists first boiled natural wood in a mixture of sodium hydroxide and sodium sulfite, to remove some of the lignin and hemicellulose, substances contained in the walls of wood cells (the former retard parasite and bacterial attacks, the latter cover and bind fibers). Then they put the wood in a hot press, which leads, as they say in the paper, “to the total collapse of cell walls and the complete densification of the natural wood with highly aligned cellulose nanofibres.” The result, they conclude, is a “low-cost, high-performance, lightweight alternative” to “most structural metals and alloys.”<p>If this decreases the burn rate, as other commenters have pointed out, and the input energy is manageable, then this has a chance. Cool!
> Teng Li, a University of Maryland mechanical engineer, created with his colleagues wood that’s as “strong as steel, but six times lighter,” he said<p>Phrases like this make me uneasy. "Strength", especially when used informally like this, is quite ambiguous (e.g. there's a reason we don't make buildings out of spider silk).<p>Overall it's quite an uplifting piece though, and I would certainly like to see such a revival.
Even if the technology is perfected and proven superior on several counts, the adoption has to overcome the psychological barrier. The places that don't have a culture of wooden buildings, especially the floor, will need some convincing.<p>As an Indian, I don't encounter wooden floor often. Modern buildings are all brick and reinforced concrete, and old temples are stone mostly. Any wooden floor one might come across are just wood panels installed on concrete floor. Nearly two decades back, the city library (Seshadri library, Bengaluru) was renovated, and as a part of it the shelves were raised and a wooden corridor was installed to enable access to higher shelves; its a tall building with a dome and a large hall under it, your typical library. Needless to say, I was quite apprehensive to walk on it, so were most people there. Apart from that, the only experience I have is standing on my desk to change the bulb. The desk is quite sturdy - the bulkier carpenter stood on it to demonstrate - but I just can't trust it the same way I trust concrete floor. When on a wooden surface, I step softly, hoping to make myself lighter, just in case, though I know its nonsense.
There are actually plans to build a 350 meter (approx. 1050 foot) skyscraper in Japan.
<a href="https://www.dezeen.com/2018/02/19/sumitomo-forestry-w350-worlds-tallest-wooden-skyscraper-conceptual-architecture-tokyo-japan/" rel="nofollow">https://www.dezeen.com/2018/02/19/sumitomo-forestry-w350-wor...</a><p>For those interested in more "concrete" expressions of the existing capabilities of timber based construction an 18 story dormitory was assembled in 70 days at the University of British Columbia.<p><a href="https://news.ubc.ca/2016/09/15/structure-of-ubcs-tall-wood-building-now-complete/" rel="nofollow">https://news.ubc.ca/2016/09/15/structure-of-ubcs-tall-wood-b...</a><p>Here's a time-lapse:
<a href="https://www.youtube.com/watch?v=GHtdnY_gnmE" rel="nofollow">https://www.youtube.com/watch?v=GHtdnY_gnmE</a>
If you can extrude or shape the densified wood, into something "branch-like" but at steel like strength then you open up new building opportunities - our cities are dominated by straight lines, for good reasons, but branchlike handrails, footpaths and arches open up a lot of possibilities for good architects to chnage the look of a city beyond the mere material it is made of
The question I have about all of this is the environmental impact of the "densification of wood." They cite it being similar to paper manufacturing, which is really energy intensive and is a horribly polluting industry.<p>I don't have any info on the above, but it is something I wonder about.
First of all, what they are talking about is more like paper made out of wood since the fibers are treated extensively and then formed. Secondly, large and spreading structure fires which have such a devastating history have been essentially eliminated by use of sprinkler systems.
I'm day dreaming about 'aktivhaus' (sp?) style residential in the desert.<p>What would that look like?<p>My starting notion is a three level structure. Bottom is carport, patio, storage. Middle would be kitchen, baths, common areas, study. Upper would be bedroom(s). Maybe a roof top deck.<p>South wall would have horizontal solar louvres. Kinda like the Burr library in downtown Phoenix.<p>Roof top solar something. But I'd still want to be able to look up at the stars.<p>Grey water system of some sort. So the ground level would have a cistern of some sort.<p>Is wood a viable option for the desert? I know zilch about thermal loads, insulation, etc. If so, how much wood?
Three out of three top comments here are about fires - an issue the article specifically talks about.<p>How about reading the whole piece instead of just a headline?
Some cities were wood, and they burned. My concrete condo is in the burn path of the 'great Ottawa fire'. Wikipedia doesn't have enough pictures, worth googling.<p><a href="https://en.wikipedia.org/wiki/1900_Hull–Ottawa_fire" rel="nofollow">https://en.wikipedia.org/wiki/1900_Hull–Ottawa_fire</a>
The case against:<p><a href="https://en.wikipedia.org/wiki/List_of_town_and_city_fires" rel="nofollow">https://en.wikipedia.org/wiki/List_of_town_and_city_fires</a>