Dripping faucets in Summerville are usually a hard water story. At 5.5 grains per gallon, mineral deposits build up on cartridges and seats until they no longer close cleanly.
Why yours started dripping
Scale forms on the cartridge and the valve seat, so the faucet cannot seal fully even when closed hard. Forcing the handle tighter accelerates the wear. A cartridge replacement fixes it, and treating the water is what stops it happening again on the same schedule.
Builder-grade fixtures in newer homes
Homes across Nexton, Cane Bay and Carnes Crossroads were fitted with entry-level faucets that are now past warranty. In hard water they wear quickly. Replacing with a better cartridge-based fixture is frequently cheaper over five years than repeated repairs on the original.
Low pressure at one tap only
Almost always a blocked aerator, and almost always mineral scale in this area. Unscrew it, soak it in vinegar, refit. If pressure is low across the whole house, that is a different problem — usually the pressure regulator — and worth a call.
Under-sink leaks
Supply connectors and drain assemblies fail slowly and quietly. On slab-built Summerville homes, cabinet water damage is often the first visible sign. Worth checking under each sink twice a year.