Yes, Cascade County Zoning Regulations (CCZR) requires all signs, structures, foundations, buildings, and changes of use to obtain a permit with Cascade County Planning Department, as mention in CCZR §9.2 under Permit Requirements:
"No future change of land use may be made; or no building, structure, sign or foundation therefore shall be erected, added to, or structurally altered until: 1) a permit therefore has been issued by the Zoning Administrator; 2) a site plan meeting the requirements of Section 8.5 of these regulations and based on the property boundaries in accordance with the legal description, as filed on record, has been filed by the Zoning Administrator, and a separate Location/Conformance Permit has been issued for each tract of land.
Location/Conformance Permits are required for all buildings (200 square feet or larger), structures (200 square feet or larger), signs, or foundations located within the Cascade County Zoning District unless otherwise specified in these regulations.
Location/Conformance Permits are required for all commercial activities including but not limited to buildings, structures, signs, or foundations that will be used for commercial activities anywhere within Cascade County exclusive of incorporated cities and towns.
Location/Conformance Permits are not required for site preparation (see Site Preparation definition) or for other Permitted Accessory Uses (including but not limited to garages, sheds, barns, or the usual agricultural buildings and structures) located on a tract of land provided only one residential dwelling unit is located on the tract, the tract of land is zoned A – Agricultural, and the tract is larger than 160 acres. However, the placement of any structures on these parcels must comply with the A Agricultural requirements listed in these regulations. All other uses including commercial, special use permits, etc. require obtaining a location/conformance permit and complying with the Cascade County Zoning Regulations. [,]" (CCZR, §9.2 Location/Conformance Permit).