Pub firm Young's applied to extend the Founder's Arms pub on Bankside, but neighbouring residents in the Falcon Point flats objected, fearing an increase in noise and antisocial behaviour, as well as loss of privacy, light and views.
The pub's owners said the plan to add an extra storey to the riverside building was necessary to ensure its long-term viability, and that the expansion would create 22 jobs.
Rejecting Young's scheme, Southwark Council planning officers said that "the proposal is deemed to result in a harmful impacts in terms of noise ... Harmful noise impacts are likely to arise from the dispersal of patrons entering and exiting [the] site from a potential additional 100 patrons".
Planners also judged that despite Young's submitting a management plan, "there still remains a high element of risk to the amenity of local residents due to the proximity of the residential flats at Falcon Point to the site" and that "the increase in patrons poses a high risk of resulting in antisocial behaviour due to the nature of the proposed use and the proposed maximum quantity of users".
The current Founder's Arms building dates from the late 1970s when it was constructed as part of the Falcon Point development.
It replaced a nearby Victorian pub of the same name that had been acquired by Young's in the 1950s.
Falcon Point was developed as council housing but many of the properties are now in private hands.