Check with the building permit authority in your area.
In my case, I needed an electrical permit.
To go without a permit where they are required is nothing any responsible person would advise you to do.
The penalty in my area for non permitted work is a fee of double the cost of the original permit, plus you have to bring the project up to code, including tearing apart existing work, or otherwise uncovering things to prove correct burial depth of footings, or wiring, or tearing down walls to inspect wiring, insulation, etc...
Totally your decision.
Brewman