Backdraft Dampers | McMaster-Carr

	For Opening		Overall							Mounting
	Wd.	Ht.	Wd.	Ht.	Dp.	Blade Thk.	No. of Panels	For Max. Air Velocity, fpm	Temp. Range, ° F	Fasteners Included	Hole Dia.		Each
Galvanized Steel Frame and Aluminum Blades



		10 1/2"	10 1/2"	13"	13"	2 1/2"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000


		12 1/2"	12 1/2"	15"	15"	2 1/2"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	00000
		14 1/2"	14 1/2"	17"	17"	2 1/2"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	00000
		16 1/2"	16 1/2"	19"	19"	2 1/2"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	00000
		18 1/2"	18 1/2"	21"	21"	2 1/2"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	00000
		20 1/2"	20 1/2"	23"	23"	2 1/2"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	00000
		22 1/2"	22 1/2"	25"	25"	2 1/2"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000
		24 1/2"	24 1/2"	27"	27"	3"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000
		24 1/2"	36 1/2"	27"	39"	3"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000
		26 1/2"	26 1/2"	29"	29"	3"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000
		28 1/2"	28 1/2"	31"	31"	3"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000


		30 1/2"	30 1/2"	33"	33"	3"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000
		32 1/2"	32 1/2"	35"	35"	3"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000
		34 1/2"	34 1/2"	37"	37"	3"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000
		36 1/2"	36 1/2"	39"	39"	3"	0.017"	1	2,500	-40 to 180	No	9/32"	00000000	000000
		38 1/2"	38 1/2"	41"	41"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000
		40 1/2"	40 1/2"	43"	43"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000
		42 1/2"	42 1/2"	45"	45"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000
		44 1/2"	44 1/2"	47"	47"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000
		48 1/2"	48 1/2"	51"	51"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000
		50 1/2"	50 1/2"	53"	53"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000


		54 1/2"	54 1/2"	57"	57"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000
		56 1/2"	56 1/2"	59"	59"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000
		60 1/2"	60 1/2"	63"	63"	3"	0.017"	2	2,500	-40 to 180	No	9/32"	00000000	000000


		304 Stainless Steel Frame and Blades



				12"	12"	15"	15"	2 3/8"	0.019"	1	2,500	-20 to 200	No	1/4"	0000000	000000


				16"	16"	19"	19"	2 3/8"	0.019"	1	2,500	-20 to 200	No	1/4"	0000000	000000
				18"	18"	21"	21"	2 3/8"	0.019"	1	2,500	-20 to 200	No	1/4"	0000000	000000
				20"	20"	23"	23"	2 3/8"	0.019"	1	2,500	-20 to 200	No	1/4"	0000000	000000
				24"	24"	27"	27"	2 3/8"	0.019"	1	2,500	-20 to 200	No	1/4"	0000000	000000
				30"	30"	33"	33"	2 3/8"	0.019"	1	2,500	-20 to 200	No	1/4"	0000000	000000
				36"	36"	39"	39"	2 3/8"	0.019"	1	2,500	-20 to 200	No	1/4"	0000000	000000

Motor Kits for Louvers with Galvanized Steel Frames

Image of Product. Front orientation. Louver Motors.

Motor kits for louvers let you open louvers when you’re not running your exhaust fan but still want to let air flow into your ventilation system.

				Overall
For Opening Wd.	Includes	Voltage, V AC	Electrical Phase	Lg.	Wd.	Ht.	Mounting Fasteners Included		Each
10 1/2" to 36 1/2"	Motor, Motor-to-Louver Arm, Mounting Bracket	120/240	Single	4 1/4"	5"	7"	Yes	00000000	0000000
38 1/2" to 50 1/2"	Motor, Motor-to-Louver Arm, Mounting Bracket	120/240	Single	6"	5"	6"	Yes	00000000	000000
54 1/2" to 60 1/2"	Motor, Motor-to-Louver Arm, Mounting Bracket	100 to 240	Single	6"	4"	6 1/2"	Yes	00000000	000000

Roof-Mount Louvers

These louvers are gravity operated. The blades open when your roof-mounted exhaust fan goes on and close when it's off, preventing backdrafts. The felt seal on the face of the blades ensures quiet closing and better protection from the weather.

Also Available: Additional louver sizes. Please select 8061T999 and specify louver dimensions.

Surface Mount


	Surface Mount	Exhaust Fan Mounts

Exhaust Fan Mounts—Exhaust fan mounts are sold separately. Louvers fit the bottom of the mount and must be secured to the lip of the mount's base with sheet metal screws (not included).

	Louvers											8" High Exhaust Fan Mounts			12" High Exhaust Fan Mounts
	For Opening		Overall
	Wd.	Ht.	Wd.	Lg.	Blade Thk.	No. of Panels	For Max. Air Velocity, fpm	Temp. Range, ° F	Mounting Fasteners Included		Each	Inside Wd.		Each	Inside Wd.		Each
Galvanized Steel Frame and Aluminum Blades



		13 3/4"	13 3/4"	13 3/4"	13 3/4"	0.016"	1	2,000	-40 to 180	No	000000	000000	14 1/2"	0000000	0000000	14 1/2"	0000000	0000000


		15 3/4"	15 3/4"	15 3/4"	15 3/4"	0.016"	1	2,000	-40 to 180	No	000000	00000	16 1/2"	0000000	000000	16 1/2"	0000000	000000
		17 3/4"	17 3/4"	17 3/4"	17 3/4"	0.016"	1	2,000	-40 to 180	No	000000	00000	—	———	0	19 1/2"	0000000	000000
		19 3/4"	19 3/4"	19 3/4"	19 3/4"	0.016"	1	2,000	-40 to 180	No	0000000	00000	21 1/2"	0000000	000000	—	———	0
		21 3/4"	21 3/4"	21 3/4"	21 3/4"	0.016"	1	2,000	-40 to 180	No	0000000	00000	—	———	0	23 1/2"	0000000	000000
		23 3/4"	23 3/4"	23 3/4"	23 3/4"	0.016"	1	2,000	-40 to 180	No	0000000	00000	—	———	0	25 1/2"	0000000	000000
		27 3/4"	27 3/4"	27 3/4"	27 3/4"	0.016"	1	2,000	-40 to 180	No	0000000	000000	—	———	0	28 1/2"	0000000	000000
		34 3/4"	34 3/4"	34 3/4"	34 3/4"	0.016"	1	2,000	-40 to 180	No	0000000	000000	35 1/2"	0000000	000000	35 1/2"	0000000	000000
		36 3/4"	36 3/4"	36 3/4"	36 3/4"	0.016"	1	2,000	-40 to 180	No	0000000	000000	—	———	0	37 1/2"	0000000	000000

Motor Kits for Louvers with Galvanized Steel Frames

Motor kits for louvers let you open louvers when you’re not running your exhaust fan but still want to let air flow into your ventilation system.

			Overall
Includes	Voltage, V AC	Electrical Phase	Lg.	Wd.	Ht.	Mounting Fasteners Included		Each
Motor, Motor-to-Louver Arm, Mounting Bracket	120/240	Single	7 3/8"	4 1/2"	8 1/2"	Yes	00000000	0000000

Fixed- and Adjustable-Blade Wall-Mount Louvers

Fixed front blades give you consistent sight lines when viewing these louvers from outside, while hidden rear blades open and close.

Recessed Mount

Recessed

Mount

Water Penetration Rating—Water penetration rating is the air velocity at which water will start to pass through the louver. The higher the number, the better protected the louver is from rain.

Pressure Drop @ Water Penetration Rating—Pressure drop is the amount of pressure lost as air passes through the louver into your system. The lower the pressure drop, the higher the airflow.

Airflow—Airflow is the volume of air passing through the louver. Your louver should allow the necessary airflow required for your HVAC system.

	For Opening		Overall
	Wd.	Ht.	Wd.	Ht.	Dp.	No. of Panels	Water Penetration Rating, fpm	Pressure Drop @ Water Penetration Rating, in. H₂O	Airflow, scfm	For Max. Air Velocity, fpm	Includes	Certification		Each
Aluminum Frame and Blades



		12"	13"	11 1/2"	11 1/2"	4"	1	1,250	0.17	175	1,250	Bird Screen	AMCA Certified for Air Performance, AMCA Certified for Water Penetration	0000000	0000000


		14"	14"	13 1/2"	13 1/2"	4"	1	1,250	0.17	438	1,250	Bird Screen	AMCA Certified for Air Performance, AMCA Certified for Water Penetration	0000000	000000
		20"	20"	19 1/2"	19 1/2"	4"	1	1,250	0.17	1,013	1,250	Bird Screen	AMCA Certified for Air Performance, AMCA Certified for Water Penetration	0000000	000000
		24"	24"	23 1/2"	23 1/2"	4"	1	1,250	0.17	1,588	1,250	Bird Screen	AMCA Certified for Air Performance, AMCA Certified for Water Penetration	0000000	000000
		36"	36"	35 1/2"	35 1/2"	4"	1	1,250	0.17	4,350	1,250	Bird Screen	AMCA Certified for Air Performance, AMCA Certified for Water Penetration	0000000	000000