U225X PUBLIC RECORD / FIX-012 TITLE: Ceiling-fan and box-fan airflow strategy STATUS: Recovered/Partial CATEGORY: Repairs / Technology TYPE: troubleshooting The recovered conversation identifies the unused attic/whole-house fan as a major heat-leak path. The recommended approach is a removable insulated cap made from 2-inch R-10 foam board, sized a few inches beyond the opening, with compatible foil HVAC or foam-board tape and weatherstripping around the contact edge. The cap must remain removable and the fan must be unable to start while covered. GOAL: Reduce afternoon heat entering through an unused attic fan without permanently altering the opening or creating a fan-start hazard. EQUIPMENT - 2-inch R-10 foam board - Compatible foil HVAC or foam-board tape - Weatherstripping - Tape measure and straightedge - Utility knife used with normal cutting precautions MATERIALS - 2-inch R-10 rigid foam board - Foam-board or foil HVAC tape - Removable weatherstripping STEPS - Measure the fan opening and note whether the fan housing rises above the attic floor. - Cut a removable foam-board panel a few inches larger than the opening on all four sides. - Build up the panel into a shallow insulated box/cap if the fan housing needs clearance. - Seal foam-board seams with compatible foil HVAC or foam-board tape. - Add weatherstripping around the contact edge so the cap seats against the framing or ceiling surface. - Verify the fan cannot be accidentally energized while the cap is installed. - Keep the cover removable and record the final dimensions for the next revision. TROUBLESHOOTING - If the cap rocks or leaks air, check the framing plane and improve the weatherstripping rather than permanently gluing it down. - If the fan housing projects above the floor, use a box/cap shape instead of forcing a flat panel against it. - Do not treat a barrier as a substitute for correcting a fan that can still be switched on while covered. - Box fans placed directly on supply registers may disturb the intended duct airflow; remove them during the comparison test. SAFETY / LIMITS - Confirm the unused fan cannot start before covering it. - Use normal cutting and attic-access precautions; avoid contact with energized wiring. - Use materials compatible with the foam board and keep the cap removable for inspection. RESULT Recovered practical barrier plan; final dimensions and fit remain the next field check. SOURCE NOTE This is a public-safe summary assembled from the local content manifest and recovered notes. It is not a raw conversation transcript. Measurements, files, and outcomes remain marked as provisional where the source did not preserve enough evidence. PROPERTY OF U225X / PUBLIC-SAFE IMPORT