Do I need a permit for garage conversion in Unincorporated Forsyth County?

Most likely yes. Garage conversion usually requires a permit in North Carolina. Confirm the specifics with Unincorporated Forsyth County.

Adding wiring, heating or cooling, plumbing, or load-bearing structure takes a garage conversion outside the $40,000 permit exemption in NCGS 160D-1110(c), whatever the project costs. Section N1109.2 of the North Carolina Residential Code covers projects that change unconditioned space to conditioned space. If the project costs more than $10,000, an extra 10 percent of the project cost must go toward energy conservation features, and wall, ceiling, or floor cavities opened during the work must be insulated. Every sleeping room needs an emergency escape and rescue opening (Section R310.1), and permitted alterations require smoke alarms and carbon monoxide alarms located as for a new dwelling (R314.2.2 and R315.2.2). Turning a garage into a bedroom, living room, office or apartment changes it to habitable space, which must meet the code for living areas, such as insulation, heating, ceiling height, light, and an emergency escape opening in any sleeping room. A conversion normally needs a building permit, and often electrical, mechanical and plumbing permits too. Zoning may also require you to keep off-street parking or limit a second unit, so check zoning before you design.