Prefab homes are built off-site in sections, while modular homes are a specific type of prefab constructed in large factory-made modules and assembled on a permanent foundation to meet the same local building codes as traditional stick-built houses. Key Differences Between Prefab and Modular Homes Explained Prefab is a broad term for homes with major parts built in a factory, including modular, panel-built, and manufactured types. Modular homes are a subset, built in large modules and assembled on-site to meet local building codes. Key distinctions to know: Prefab: Factory-built panels or smaller sections; quality and code standards vary. Modular: Fully built modules with wiring, plumbing, and finishes; meets same codes as stick-built. Manufactured: Built to HUD code, often movable, not the same as modular. Site adaptability: Prefab can handle narrow or remote access more easily. Durability: Modular often excels in strength and weather resistance. Understanding these differences helps you choose the option that fits your priorities, whether it’s design flexibility, code compliance, or resilience in storm-prone areas. Once you know the basics, the real value comes from seeing how these two options compare in cost, durability, efficiency, and design potential, so you can match your choice to your lifestyle and