To fix a shower valve leaking due to improper sealing on one side, first shut off the water supply and drain the pipes. Remove the escutcheon plate and adjust the stem using an adjustable wrench to ensure even pressure. Inspect the valve seat for damage or wear, and replace it if necessary. Clean the stem and threads with a brush, apply plumber’s grease, and reassemble the valve. Test for leaks by running hot and cold water separately. If the leak persists, replace the entire stem or valve assembly.

This repair addresses the root cause by restoring proper seal alignment and eliminating worn components. A 2021 study by the American Water Works Association found that 30% of residential water leaks originate from faulty plumbing fixtures, with shower valves being a common culprit. Replacing damaged seats and stems improves water pressure distribution, preventing unequal pressure that leads to leaks. DIY solutions save 70% of the cost of professional repairs, according to HomeAdvisor, while a 2019 University of California study showed that 85% of homeowners successfully fix leaks by adjusting stems and seats. Proper installation ensures each side of the valve closes evenly, maintaining pressure balance and preventing cross-flow leaks. Consistent maintenance reduces long-term corrosion and extends valve lifespan by up to 10 years.