MILWAUKEE, Wisconsin — An apartment tower planned for downtown Milwaukee is nearly doubling in height, and would be among the world’s tallest mass timber buildings when it opens in 2025. The Edison was initially planned as a 15-story building with around 200 units overlooking the Milwaukee River. But revised plans that have just been filed with the city now call for a 28-story high-rise with 296 apartments, said Nate Helbach, at The Neutral Project LLC. …The Neutral Project decided to expand its plans for The Edison because of the economies of scale achieved with a taller high-rise, Helbach said. ..Construction work on the high-rise is to begin this fall, with The Edison to be completed by fall 2025. …Apartments made from timber provide a lower carbon footprint than conventional construction. They also can create a more attractive atmosphere, featuring exposed wood interiors.