The tallest mass timber building in the world is the Ascent building in Milwaukee, which stands at 284.1 feet tall. One of the biggest wooden structure in the world, Todai-ji Temple in Nara, Japan.Look at the size of the human beings at the entrance for comparison. Pioneer has been around for 40 years and has become the largest builder of handcrafted log homes in the world. The following is a complete list of mass timber buildings worldwide, eight stories and higher.