More than half the world’s population dwell in cities, and by 2050 the un expects that proportion to reach 68%. This means more homes, roads and other infrastructure. …Such a construction boom does, though, bode ill for tackling climate change, because making steel and concrete generates around 8% of the world’s anthropogenic carbon-dioxide emissions. As it happens… as architects have become increasingly interested in modern timber-construction methods, wooden buildings have been getting steadily taller.  As the AAAS meeting heard this week, wood is one of the most promising sustainable alternatives to steel and concrete. It is not, however, everyday lumber, chipboard or plywood that is attracting the interest of architects. Rather, it is a material called engineered timber.  …If building with wood takes off, it does raise concern about there being enough trees to go round. But with sustainably managed forests that should not be a problem, says Dr Ramage. [We respect the copyrights of the source publication – full access may require a subscription]