This three-chapter guide shows you how to plan, build, and finish a barndominium the right way. First, you secure the project on paper: define use and code path, select post-frame or red-iron structure, choose the right foundation, and solve moisture with a real thermal break and air seal. You set a realistic budget, schedule long-lead items, and submit a complete permit packet with stamped drawings and energy sheets. Next, you build a square, watertight shell. You establish control points, compact the pad, place a slab with a vapor barrier and proper joints, and set anchors. You erect frames with tight bracing, install roof and wall panels in straight, sealed lines, flash openings, control condensation, and move water away from the base. You pass foundation, framing, and roof inspections before closing. Finally, you complete systems and finishes for comfort and compliance. You insulate to control dew point, frame rated separations to isolate the shop, and rough electrical, plumbing, and HVAC with labeled runs and tests. You air-seal, close walls, set floors and cabinets, install fixtures and appliances, and commission the home with blower-door and duct tests. You wrap with a punch list, documentation, and a simple maintenance plan. The outcome is a code-compliant, efficient barndominium built with clarity, safety, and confidence.