The International Building Code and the International Residential Code have slightly different requirements for when permits are required.
The International Building Code (IBC)
The International Building Code Section 105.1 states, "Any owner or authorized agent who intends to construct, enlarge, alter, repair, move, demolish, or change the occupancy of a building or structure, or to erect, install, enlarge, alter, repair, remove, convert or replace any electrical, gas, mechanical or plumbing system, the installation of which is regulated by this code, or to cause such work to be done, shall first make application to the building official and obtain the required permit."
Exceptions
There are some exceptions, which you will find under the IBC Exempt Work (PDF) provision in the Arlington Municipal Code, Chapter 15.08, Section 105.2.
The International Residential Code (IRC)
The International Residential Code Section R105.1 states, "Any owner or authorized agent who intends to construct, enlarge, alter, repair, move, demolish, or change the occupancy of a building or structure, or to erect, install, enlarge, alter, repair, remove, convert or replace any electrical, gas, mechanical or plumbing system, the installation of which is regulated by this code, or to cause such work to be done, shall first make application to the building official and obtain the required permit."
Exceptions
There are some exceptions, which you will find under the IRC Exempt Work (PDF) provision in the Arlington Municipal Code, Chapter 15.08, Section R105.2.