Duvall Municipal Code Title 10, Building and Construction, Chapter 10.01 Construction Codes, requires that any owner or authorized agent who intends to construct, enlarge, alter, repair, move, demolish, or change the occupancy of a structure. A permit is also required to erect, install, enlarge, alter, repair, remove, convert or replace any electrical, gas, mechanical or plumbing system, the installation of which is regulated by Chapter 10.01, or to cause and such work to be done, shall first make application to the Building Official and obtain the required permit.