What is the minimum required separation between garages and habitable rooms directly above them?

The minimum required separation between garages and habitable rooms directly above them is defined by fire safety codes, which aim to prevent the spread of fire and provide adequate protection for living spaces. In this context, Type X gypsum board is a fire-rated material that helps create a barrier between the garage—a space that could contain flammable materials—and the habitable rooms above.

Using 1-inch Type X gypsum board meets the minimum requirement established by building codes, as it provides sufficient fire resistance to delay the spread of flames and heat, ensuring a safe environment for the occupants in the rooms above. This choice is effective in achieving adequate protection without excessive material use or concern about structural integrity.

The other options specify greater thicknesses of gypsum board, which, while potentially providing additional fire resistance, are not necessitated by code for minimum requirements and may result in increased construction costs and labor without proportional benefit to safety standards in this particular context.