We are considering purchasing a mobile home or a modular home. I know that the difference between a mobile vs a modular is that a mobile home is on a steel frame and is built to HUD code, whereas a modular is built to local building codes and IRC.

However, what are the specific differences between these codes?

When comparing a brand new mobile home that costs $60/sq ft, vs a new modular that costs $95/sq ft, why does the modular cost more? Assume these prices both exclude installation, foundation, transportation, and utility hookups; so these prices are referring only to the building itself. I'm looking for specific reasons why one is so much cheaper:

• How is the HVAC different?
• Are the exterior / interior studs different sizes?
• Is the sheathing different?
• Is the flooring material different?
• Is the window flashing different?
• Assuming both homes have a metal roof, is the metal roof a different gauge?
• Is there more insulation in the modular?
• Are the countertops different materials?
• How is the workmanship different?

I spoke with 2 manufacturers so far who are selling at $83/sq ft and up, they are telling me that all mobile homes now adays come with double pane argon-gas-filled vinyl or aluminum windows, 2x4 exterior wall studs 16" OC, R-13 insulation in the walls, known name-brand HVAC, OSB sheathing, flashed windows, shingle or metal roofs, etc.

So why/how is the mobile able to be built as low as $60/sq whereas a modular cannot be built lower than $95/sq ft? Where is the cost difference coming from? If I were to take the siding and roofing off both homes (both being manufactured in 2024 or 2025) and look at the construction and materials, what differences would I see?