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Comment by metalman | Hacker News Reader

There is a great deal of prior art in aviation and automotive engineering for densified wood, which have all proven to be non competitive with metal. Lighter, stronger, but not quickly adaptable to new designs or refinements.....the molds are large, complex, heavy, and expensive. And a simple no go for beams is that they(wood) burns and steel does not, will instantly remove them(wood) from bieng used in most building codes past a certain hight, where minimum times for evacuation durring a fire can not be met.

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One of the reasons why Ipe (pronounced “e-pay”) wood is so fire resistant, is because of its density. You can get Class-A fire resistant Ipe that can be used to build in the Wildland/Urban Interface environment. Other woods like Teak and Rock Maple are also super dense, but I don’t know if you can get them in Class A ratings.

Now, Ipe is very expensive. I would hope this is less expensive than Ipe, and then the trick is to make your starting materials much larger, and being able to account for the shrinkage once the densification process has been completed.

You could also do laminates of this densified wood, in order to be able to use it for beams, plywood type functions, etc…. Or even fire resistant 2x4 boards.

I was under the impression that mass timber buildings were actually safer for fires because it takes a very long time to burn through, and unlike steel they won't lose their strength in an intense fire.

what maters is time to escape befor "total involvement", or confaguration, steel contributes nothing to a fire, fire cant climb or follow it, and it acts as a heat sink, vs wood, which is fuel. All of the historical mass casualty fire storms, involved wooden structure, and steel, concrete,glass, and brick, ended that. Add in modern fire suppresion and fighting equipment and the current situation is quite secure vs/vs fire. edit, another factor is comunication and road infrastructure, where the recent fire storm in California, destroyed many many wooden structures, but the loss of life was exceptionaly low compared to other firestorms in less developed countrys. woods great, love the stuff, have a lot of wood, live in a wooden house and heat with wood, but there is essentialy no way that can be done with a thousand people in a huge building, so steel, which I also love and work with. Everything in it's place.

"total involvement", or confaguration, is what matters true. However fires are more complex than that. Generally the wood frame isn't a source of fuel for the fire until later. The carpet and other furniture that is the same in all builds is likely to burn first. Not long after the wood frame is burning the steel frame absorbs enough heat to fail - but either way you really want to be out long before it gets that bad (and probably are dead if you are not)

> All of the historical mass casualty fire storms, involved wooden structure, and steel, concrete,glass, and brick, ended that.

You're right insofar as lots of improvements have been made to steel-and-concrete building fire safety since the 1970s. Plastics are sometimes still a problem.

https://en.wikipedia.org/wiki/Grenfell_Tower_fire

https://nfsa.org/2023/08/22/understanding-combustible-materi...

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