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Province to allow 12-storey buildings made of wood

I like the change to this policy. It's obvious that wood and concrete have there different strengths and weaknesses, but I believe that this will encourage a little more mid-density development not only in the city but in the surrounding area, as constructing a building out of wood is cheaper than concreate.
 
There are some really game-changing advancements in wood construction: 1. Cross-laminated timber is actually more structurally sound than steel in extreme heat conditions. This method has been employed in the Scandinavian countries since the '90s and underscores other properties as well -- for those who are interested -- https://info.thinkwood.com/clt-handbook; 2. advancement in the Japanese artform Shou Sugi Ban -- https://nakamotoforestry.com/?gclid=EAIaIQobChMIwaWnrLau5wIVfCCtBh3-uQDbEAAYASAAEgKdXPD_BwE which employs an artful way of charring wood and thereby making it fire resistive; and 3. a new wood formula that makes wood stronger than steel -- https://www.smithsonianmag.com/smar...-makes-super-dense-and-strong-wood-180968117/
 
@archited A local architect was doing some experiments with carbonized wood, similar in concept to Shou Sugi Ban but I think with a slightly different technique employed. I think he was using it more for architectural rather than structural purposes, but I'm curious how it's holding up.
 
@Daveography I am quite sure that it was a design choice in the case of the historical use of SSB in Japan. There are three levels of application for the art and, (currently the names for each escape me ) so the most charcoal-intense form -- completely and deeply charred -- is the only one that is truly fire resistive (I say "resistive" because under intense heat I suspect the wood would reignite in unpredictable ways); the second involves sanding the char to remove the "pebbling effect" but keeping the wood fairly dark; the third involves sanding to the point that only the soft grain is blackened and the hard grain gets a natural-wood-color sheen. For furniture applications the third is quite beautiful; for interior wall finishes, the second takes the prize; exterior finishes are best suited to number one, the full char treatment. It would be cool to see a few SSB houses in Edmonton. I have done a few of these in interior bar atmospheres in SoCal using a blow torch and belt sander (not at the same time ? ) to achieve the ideal effect.
 
I'm all for it. Ironically I have a feeling wood buildings will be safer especially if they have an innate fear of fire built into them. Maybe people would stop being so careless when it comes to fire which let's face it is the cause of the vast majority of blazes.. How many times do I have to hear about a tossed cigarette lighting a planter/BBQ/patio set/cladding on fire and it causes millions of dollars in damage... Safety or at least a perception of safety tends to make people more careless and ignorant... Case in point... Too Much Safety...
 
https://resources.impactfireservices.com/workplace-fire-safety-complete-plan-protecting-lives-assets/?hsCtaTracking=43f79f86-7c87-4c0e-b750-f4b23573d716|2fdcc84c-4bdb-4df0-b0d0-3d8fe7062c46 -- As you can see from this review, most office fires (like home fires) start in a kitchen, typically not from smokers who are now often banned to outdoor areas. Mass-Timber structures are actually more fire resistive than steel structures from a structural integrity point of view and that is why their use is being re-upped. Surface burning on wood timbers creates a charcoal barrier to further burning damage, allowing more time for people to evacuate in a serious fire. Some places -- Sweden for example -- allow for even higher structures than 12 floors. Of course there is the limitation of structural capacity that reins in unlimited height. New research is producing wood products that are even stronger than steel, so the future is potentially wooden 🧐
 
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The supporters of this policy have raised good points here. I'm in favour of it, but not just because of the cost factors. Concrete production is seriously bad for the environment, and metal isn't so good either. Carbon will be trapped in the wood until the building comes down, meaning that the buildings are at least a bit more balanced with the carbon cycle.
 
Daveography said:
@archited A local architect was doing some experiments with carbonized wood, similar in concept to Shou Sugi Ban but I think with a slightly different technique employed. I think he was using it more for architectural rather than structural purposes, but I'm curious how it's holding up.
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The Wood Innovation Design Center in Prince George, (which was the tallest wood building in North America at the time of its completion in 2016) features Shu Sugi Ban exterior façade panels. They have, for the most part, not held up very well. Especially on the South side of the building, the charcoal has flaked off on quite a few panels, leaving the building looking rather aged. That said, I heard that due to time and financial constraints the GC ended up performing the burning of the panels onsite in a rushed, non-traditional manner with a blow torch (this is purely word of mouth). I suppose the panels would have likely faired better had they been done correctly. I think at this point I could see the panels needing to be replaced in the next 5-10 years. Honestly though, it's a great look IMO. Would love to see more of it, albeit perhaps in less harsh conditions - sheltered and/or smaller scale applications.
 
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archited said:
https://resources.impactfireservices.com/workplace-fire-safety-complete-plan-protecting-lives-assets/?hsCtaTracking=43f79f86-7c87-4c0e-b750-f4b23573d716|2fdcc84c-4bdb-4df0-b0d0-3d8fe7062c46 -- As you can see from this review, most office fires (like home fires) start in a kitchen, typically not from smokers who are now often banned to outdoor areas. Mass-Timber structures are actually more fire resistive than steel structures from a structural integrity point of view and that is why their use is being re-upped. Surface burning on wood timbers creates a charcoal barrier to further burning damage, allowing more time for people to evacuate in a serious fire. Some places -- Sweden for example -- allow for even higher structures than 12 floors. Of course there is the limitation of structural capacity that reins in unlimited height. New research is producing wood products that are even stronger than steel, so the future is potentially wooden 🧐
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I made the following post (below) on Reddit in response to someone questioning the safety of mass timber in the context of fire resistance - it basically echos your comment. Stringent fire ratings are achievable with mass timber, and they can certainly be as safe as steel structures, if detailed correctly.

Here is a link to paper discussing the charring rate of mass timber floor plates: https://library.fpinnovations.ca/en/permalink/fpipub52833. This is just one of numerous full scale fire tests that have been performed showing that, as mass timber elements char in a fire event the char layer protects the inner structure of the wood. Using a standardized charring rate (.65mm/min, per the most recent Canadian wood design code), mass timber structural elements (beams, columns, walls, floors etc.) can be designed to achieve 2 hour fire ratings and better, as required by the building code. In the event that a developer or architect is still weary about exposed wood, mass timber elements can be encapsulated with gypsum (drywall) to provide even further fire resistance. Papers like this show that mass timber structures can be designed to meet fire code regulations. If you want to read similar studies on other types of mass timber products, I suggest visiting the Forest Products Innovations website - throughout their website they link to their internal database of resources, which includes numerous studies that have been performed on the behavior of mass timber in fire.

All this said, yes, there is certainly lots in store for the future of mass timber, although I do think there's a limit to what we can achieve with height. Over a certain height threshold (~15-20 storeys) it starts to become uneconomical and inefficient to design purely with mass timber. If we want to achieve real height with mass timber, then hybrid timber/steel or timber/concrete will be the way to go for the foreseeable future (akin to Brock Commons in Vancouver or the HoHo tower in Vienna). Hoping Edmonton can join the mass timber revolution soon!
 
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