Pursuant to T.C.A. 62-6-103 State of Tennessee requirements of homeowner permits:
A homeowner of a residential property may perform work themselves, without a contractors license, as long as the residential structure is not open to the public; or for sale, lease or rent.
Allowed one homeowner permit once every two (2) years.
Anyone hired by the property owner is required to be licensed if they perform $25,000 or more of the work, as these contractors would be considered prime contractors since they are contracting directly with the owner.
Any Electrician or Plumber hired by the property owner is required to have a license for any and all work performed. A Limited Licensed Electrician (LLE) or Limited Licensed Plumber (LLP) are required for work performed $25,000 or less, a Contractors license with a (CE) for electrical or (CMC) for work performed $25,000 or higher.
Other than EPA Certifications there are no specific license for HVAC projects, less than $25,000. Projects $25,000 or more must obtain a Contractors license with the (CMC classification).