Construction is about to begin on this vacation home in south central Michigan. The site is at the top of a picturesque, heavily wooded valley. The interior of the house follows the slope of the terrain in a series of terraced levels. The main volume of the house is crossed by a secondary volume which accommodates an open staircase, screened porch, and master suite. Broad expanses of glass are enabled by the rare privacy of the site. A sense of balanced logic will be instilled by the use of a three foot organizing module that set the sizing of rooms, flooring, doors, and windows. Radiant heat below the porcelain clad floors will be powered by a geothermal system and the building’s envelope is being detailed to the highest of energy efficiency standards.    The key materials of the house – obsidian black cement board siding, and charred cedar trim – were selected for their minimal carbon footprint and maintenance requirements but also to allow the house to serve as a quiet backdrop for the natural beauty of the site.