San Francisco Dual Dryer Vent Cleaning & Inspection

## Two-Dryer Exhaust Service in San Francisco, CA Dryer Vent Specialists was called to a San Francisco residence to service two dryers in the same home. Both exhaust systems received a full cleaning and inspection, covering the complete duct path from the dryer connection to the exterior termination. Lint accumulation was cleared from each system using rotary brush equipment, restoring airflow and reducing fire risk for both units simultaneously. ## Transition Duct and Foil Duct Conditions Noted One of the systems uses a UL 2158A-rated transition duct, which is the correct fire-rated flexible connector type for the short connection between the dryer and the rigid duct run. A separate system was found to use a foil flexible duct. While the foil duct was thoroughly cleaned and confirmed to be intact and properly connected during this visit, foil accordion-style duct is not considered a long-term compliant solution. Per IRC M1502.4.2, transition ducts must be a single length, listed, and manufacturer-approved. Replacement with UL 2158A-listed semi-rigid metal or approved transition duct is recommended at the next service interval to bring that system fully in line with current standards. ## Fence-Mounted Terminations Both dryer exhaust systems terminate through a perimeter fence rather than through an exterior building wall, which is an unconventional installation. The terminations were inspected and confirmed to be securely mounted and functional, with exhaust discharging to the outside as required by IRC M1502.2. While fence-mounted terminations are not the standard configuration, the critical requirement is that exhaust vents independently and conveys moisture to the outdoors, which these terminations do accomplish. The condition was documented for future reference, and no immediate remediation was required based on current functionality. ## Outcome Both dryer exhaust systems were left clean and flowing at the completion of this appointment. The foil duct on one system was cleaned and secured but flagged for future upgrade. Termination conditions were documented with photos. Homeowners in San Francisco with multiple dryers or unconventional duct routing benefit from annual inspections to catch lint buildup and installation concerns before they become safety hazards.