Multifamily air leakage testing

[Sifu]

I have a 4 story above grade plane R2. The way I read the energy code they are not required to conduct leakage testing since they are considered a commercial building in the eyes of the IECC, and they can choose to follow the prescriptive requirements of IECC 402.5.1 through 402.5.8. But, if they were 3 stories above grade plane they would be required to have testing. Am I reading this correctly?

 

[mtlogcabin]

You are correct
2018 IECC
COMMERCIAL BUILDING. For this code, all buildings that are not included in the definition of “Residential building.”