We can certainly help you size an exhaust fan. The problem is we do not have enough information at this time. Please call 1-800-GRAINGER and ask to speak to a "HVAC TECHNICAL SUPPORT SPECIALIST", and we can assist you further.
Grainger Item #: 3HHR4 Economy Ceiling Shutter, Gravity Operated, Single Panel, Fits Fan Dia 36 In, Opening Required 34 x 34 In, Length 36 In, Width 36 In, Frame Depth 1 19/32 In, Open Depth 5 1/4 In, Flange Width 1 1/2 In, Free Area 7.293 Square-Ft, Max Velocity 1500 FPM, Horizontal Mounting Position, Blade Material White Painted Aluminum, Extruded Aluminum Frame and G-90 Galvanized Tie Rod, For Use With 36 In Whole House Fans
We certainly have fans and louvers that will work for you. At this point we would need more information to get you the correct product. You can call your local Grainger and ask to speak to HVAC TECH SUPPORT and they will help you further.