Hm, mg - why not do just the teeniest bit of research before posting? It might stop you looking like an ass.
Concrete production accounts for around 10 per cent of CO2 emissions. When it's done with, you have to grind it up and use it for hardcore or landfill.
Wood locks in CO2, and the longer the house stands, the longer the CO2 stays locked in. When you've finished with it it can be pulped or shredded to make building sheets, turned into paper or burned.
Concrete is inflexible and ugly; wood is flexible and inherently attractive.
And, in an earthquake or storm, I know which building I'd rather be in. Look at Kobe after the quake in the early 90s - the wooden buildings remained standing; the concrete ones collapsed.