System work is often regulated
Changes to electrical, plumbing, gas, structural and fire-safety systems commonly sit inside local code and permit frameworks.
Repair and replacement can be treated differently
Like-for-like service work may be treated differently from relocation, enlargement or system alteration.
Ask who obtains the permit
The contract should make responsibility clear when a permit is required.
Keep final records
Approved permits, inspection documents and certificates can matter at resale, insurance review or future renovation.
Safety boundary. General planning information only. Do not open, dismantle or work on hazardous electrical, gas, structural, fire-protection or contaminated-water systems unless you are appropriately qualified and authorized.