Los Altos Dryer Vent External Wall Penetration & Cleaning

## What We Found in Los Altos Our technician arrived at a renovated Los Altos laundry room featuring two front-load dryers installed side by side beneath custom cabinetry. The installation looked clean from the outside, but a closer inspection behind the units revealed serious problems. The primary exhaust duct was completely disconnected from the dryer's exhaust outlet, meaning hot, lint-laden air had been blowing directly into the wall cavity rather than to the exterior. This is a violation of IRC M1502.2, which requires the exhaust system to convey moisture and combustion byproducts entirely to the outdoors. Heavy lint and dust accumulation on the surrounding walls, floor, and duct surfaces confirmed the system had been operating in this condition for an extended period. ## Severity of the Lint Buildup The interior of the main dryer vent duct was severely clogged with compacted lint, leaving only a small central opening for airflow. Lint accumulation of this magnitude dramatically restricts exhaust volume, causes dryer run times to increase, and raises operating temperatures inside both the appliance and the ductwork. The combination of a disconnected duct and a fully restricted exhaust path represented an active fire hazard. The flexible duct behind the unit also lacked proper support and showed poor routing geometry, further compressing airflow through the system. ## Work Performed: External Wall Penetration and Full System Restoration Our journeyman technician performed a complete dryer vent service that included establishing a proper external wall penetration to provide a dedicated, code-compliant exhaust path to the exterior. The space behind both dryers was thoroughly cleaned, removing the heavy lint and debris that had accumulated from the disconnected duct condition. The exhaust duct was reconnected and properly secured. All duct joints were oriented in the direction of airflow and fastened per IRC M1502.4.2, and metal foil tape rated for dryer use was applied at connections. The duct routing was corrected to eliminate unnecessary bends and improve airflow efficiency through the system. ## Outcome and Fire Safety Restored With the external wall penetration complete and the exhaust system properly connected through to the exterior, both dryers now vent safely and efficiently. Removing the compacted lint from the duct interior and the surrounding space eliminated the immediate fire risk. Homeowners in Los Altos with side-by-side dryer installations should schedule annual dryer vent inspections, as the confined space behind stacked or paired appliances makes disconnection and lint accumulation especially easy to miss during routine maintenance.