Electrical

If you are adding lights or electrical fixtures, you may wish to use an extension. To keep it tidy, you can learn here how to bury extension cord

On furnaces, there are many components. While you use an expert most often, you can learn why a combustion air switch failed to close, and what you can do.

As long as outlets are on a 15-amp circuit. You can use 14/2 wire for outlets. 14/2 wire will not be enough if the outlets are on a 20-amp circuit. On 20-amp circuits, you’ll need to upgrade to 12/2 wire for all outlets.

A supply duct should not be used for cable runs. Plenum-rated cables are meant for commercial facilities where the region above the drop ceiling is only used as a return air and can run via return ducts.