What thickness of gypsum board is recommended on the garage side to separate it from the residence?

The recommended thickness of gypsum board on the garage side to separate it from the residence is 5/8 inch. This specification is based on fire safety regulations, which require that any wall separating a garage from living spaces be equipped to withstand the heat and potential flames that may originate from a garage fire. The 5/8 inch thickness of gypsum board provides a higher level of fire resistance compared to thinner options.

In most building codes, such as those adopted from the International Residential Code (IRC), the 5/8 inch gypsum board is identified as Type X, which is specifically designed to offer increased fire resistance through its density and materials. The other thicknesses, such as 1/2 inch, 3/4 inch, and 1 inch, do not meet the regulatory requirements or may not provide the same level of fire-resistant protection that is necessary for this critical separation.

Therefore, using 5/8 inch gypsum board ensures safety compliance and enhances the protection between the garage and living areas, ultimately mitigating the risks associated with potential fire hazards.