As with most of our projects that take advantage of passive solar heating, the floor plan was elongated along the East-West axis to take advantage of the southern exposure. The living space and one of the bedrooms are located along the south wall and have the appropriate glazing to take advantage of the sun. The garage, which will serve primarily as a workshop is on the north side to buffer the conditioned space from the cold northern exposure. The mechanical space is centrally located to be accessible from the garage but also to keep the plumbing runs short for the hydronic radiant heat.. An airlock entry keeps cold winter air from directly entering the heated space.