The glass beside the fireplace is roughly 9 feet wide by 5.5 feet tall. The unit on the right is roughly 12 feet wide by 5.5 feet tall. They are insulated glass units held with top and bottom aluminum channels that are flush with the wood. If you only consider the window unit as the glass and the aluminum channels, estimates would likely be under $100 per square foot range.
Oglesby Greene Architects