For minor surface-level issues, some homeowners can manage basic repairs. Cleaning a blocked aerator, replacing a shower head or tightening a loose connection are tasks that don’t require a licensed plumber.
However, replacing a ceramic disc cartridge or O-rings inside the tap body requires the right tools, the correct replacement parts and a solid understanding of how to isolate the water supply safely. If you’re not confident, or if the drip persists after a DIY attempt, it’s best to call a licensed plumber. Getting it right the first time avoids more leaks and more cost down the track.