The ShutterCover™ Trim to Fit Whole House Fan Cover
Many of you have an open window in your house and don't even know it, the shutters on your whole house fan. The louvers on the fan are not airtight or insulated. Heated room air escapes through them in the winter and heat radiates through them in the summer. The SHUTTERCOVER TRIM to FIT helps eliminate air infiltration. It attaches to whole house fan shutters without going into the attic.
Never cover ventilation for providing make up and combustion air for gas fired appliances. Obstructing make up and combustion air starves oxygen from gas fired appliances and could result in the production of carbon monoxide which is a poisonous gas.
