- Opening width and height
- Door area and span influence section construction, reinforcement, track layout, spring sizing, material handling, and the documented configurations available for the project.
- Headroom and ceiling obstructions
- Low ceilings, beams, ducts, lighting, heaters, storage racks, and sloped roofs can change the lift arrangement, rear supports, and installation access.
- Window configuration
- Glazing size, placement, pane type, frames, and retainers affect section layout, finished weight, reinforcement selection, privacy, daylight, and exterior appearance.