The provisions of the International Residential Code are applicable to one- and two-family dwellings and townhouses a maximum of how many stories above grade plane?

The provisions of the International Residential Code (IRC) are applicable to one- and two-family dwellings and townhouses that are a maximum of three stories above grade plane. This limit is established to ensure that the regulations applicable to these types of residential buildings provide safety, accessibility, and structural integrity, while also considering the complexity that arises with taller structures.

By capping the maximum height at three stories, the IRC allows for a balance between promoting residential development and maintaining a manageable level of code compliance for builders and owners. One- and two-family dwellings and townhouses are typically designed to be simpler in construction and easier to navigate than larger multifamily buildings, which are subject to more stringent requirements and higher standards due to their increased occupancy and complexity.

With this understanding, recognizing that buildings exceeding three stories often require different construction methods and safety measures is crucial. This transition into more complex structures justifies the separation in code requirements and emphasizes the importance of adhering to the specific provisions outlined for different building types as determined by the IRC.