Re:As Mass Timber Takes Off, How Green Is This New Building ...
by lorenb on Friday May 31, 2019 @08:33AM
(#20060259)
You’re thinking of I-joists, which are a kind of engineered lumber, not a kind of mass timber. And those do light up like kindling. The glue used in glulams and the like chars at the same rate as the wood, and it’s pretty easy to achieve known fire ratings simply by making the members a little chunkier than they need to be since the char rate is known.
Re:As Mass Timber Takes Off, How Green Is This New Building ...
by Tharkun on Friday May 31, 2019 @08:41AM
(#20060310)
There are various ways of joining large amounts of wood together. CLT uses glue. Brettstapel uses wooden dowels (using two kinds of wood with a different hardness, so the dowels stay in place). I'm sure there are other variants as well.
Firefighters do not enter new construction homes in the US because they often use these as floor joists. The time until failure has been greatly reduced compared to older homes. Things may have gotten better in the last few decades, but I'd like to see the data.