In fact, there is so much exposed and unpainted wood, in columns, beams and ceilings, it gives the condos the appearance of a construction zone. Half the condos, which range from $800,000 to $1.3 million, have sold since the building opened last spring, said Ben Kaiser, the developer.

Mr. Kaiser faced challenges getting Carbon12 built. The permitting process took almost two years to wind through city and state agencies, largely because wood buildings in Oregon could top out at no more than six stories, he said.

In the end, officials concluded that wooden high-rises could help revive Oregon’s stagnant timber industry, Mr. Kaiser said. In August, the state increased the height limit to 18 stories.

Carbon12’s timber, however, did not come cheap, according to Mr. Kaiser, whose offices were also built with timber. Indeed, at $11 million, Carbon12 was about 20 percent more expensive to construct than a concrete version would have been, which in some ways dictated that it be a luxury condo.

“It’s like anything — the first iPhone, the first flat-screen TV,” Mr. Kaiser said. “Costs are high because not enough people are doing it.”

Nevertheless, he plans to use wood from now on. In addition to their green benefits, he said, wood buildings perform well in earthquakes because of their lighter weight and flexibility.