Timberline Lodge, a mountain lodge and resort hotel, is a four-story structure of about 40,000 square feet. The ground-level exterior walls are heavy rubble masonry, using boulders from the immediate area, and heavy timber is used from the first-floor up. The central head house section is hexagonal and sixty-feet in diameter, with a six-sided stone chimney stack ninety-feet high and fourteen-feet in diameter. Each of the six fireplace openings—three on the ground floor, three on the first floor—is five-feet wide and seven-feet high. Two wings, running west and southeast, flank the head house. Oregon woods used throughout the building include cedar, Douglas fir, hemlock, western juniper and ponderosa pine.