North Carolina Building Contractor License Practice Exam

What is the standard width for most interior doors?

1. 24 inches

2. 28 inches

3. 30 inches

4. 32 inches

The correct answer is: 30 inches

The standard width for most interior doors is indeed 30 inches. This size is commonly used because it strikes a balance between accessibility and space within a home. A 30-inch door provides sufficient clearance for people to pass through comfortably while also allowing for the efficient use of space in rooms. This dimension is particularly relevant in residential construction, where many building codes specify that a minimum clear opening width of 32 inches is required for various types of doorways to ensure accessibility, especially for individuals using wheelchairs or other assistive devices. While interior doors can be found in other widths, 30 inches is a widely accepted standard that caters to typical room sizes and ensures ease of movement. Understanding the standard dimensions helps contractors and builders ensure compliance with building codes and accessibility standards while also making informed choices regarding the design and usability of living spaces. Such knowledge is crucial for maintaining quality and functionality in construction projects.