Roof Curbs | McMaster-Carr

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REACH Compliant

	Motor Speed Motor Speed

875 rpm

	Volume Volume

	Motor Enclosure Type Motor Enclosure Type

Open Dripproof (ODP)

Totally Enclosed

	Housing Material Housing Material

Aluminum

Steel

	Number of Speeds Number of Speeds

Variable

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91 Products

About Exhaust Fans

About Sound Levels

Measured in decibels (dB), volume ratings indicate how much noise equipment makes. Some common volume levels include a whisper @ 20 dB, a refrigerator @ 40 dB, a conversation @ 60 dB, and a light machine shop @ 90 dB. OSHA recommends hearing protection for exposure to 80 dB and greater.

Roof Louvers

Louver

Surface Mount

Mounting Base

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.

Mounting bases are sold separately. Louvers fit the bottom of the mounting base and must be secured to the lip of the base with sheet metal screws (not included).

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

For technical drawings and 3-D models, click on a part number.

Louvers
For Opening		Overall							8" Overall Ht. Mounting Bases			12" Overall Ht. Mounting Bases
Wd.	Ht.	Wd.	Lg.	For Max. Air Velocity, fpm	Temp. Range, °F	Mounting Fasteners Included		Each	Inside Wd.		Each	Inside Wd.		Each
Surface Mount
Galvanized Steel Frame and Aluminum Blades
13 3/4"	13 3/4"	13 3/4"	13 3/4"	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"	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"	2,000	-40° to 180°	No	000000	00000	__	000000	00	19 1/2"	0000000	000000
19 3/4"	19 3/4"	19 3/4"	19 3/4"	2,000	-40° to 180°	No	0000000	00000	21 1/2"	0000000	000000	__	000000	00
21 3/4"	21 3/4"	21 3/4"	21 3/4"	2,000	-40° to 180°	No	0000000	00000	__	000000	00	23 1/2"	0000000	000000
23 3/4"	23 3/4"	23 3/4"	23 3/4"	2,000	-40° to 180°	No	0000000	00000	__	000000	00	25 1/2"	0000000	000000
27 3/4"	27 3/4"	27 3/4"	27 3/4"	2,000	-40° to 180°	No	0000000	00000	__	000000	00	28 1/2"	0000000	000000
34 3/4"	34 3/4"	34 3/4"	34 3/4"	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"	2,000	-40° to 180°	No	0000000	000000	__	000000	00	37 1/2"	0000000	000000

Direct-Drive Downdraft Roof-Mount Exhaust Fans

Direct-drive fans have fewer moving parts than belt-drive fans for less maintenance. More economical than upblast roof-mount exhaust fans, these draw stagnant and humid air out through your roof and then direct it back toward the roof. All fans have a disconnect switch to turn off the power for servicing.

Note: Airflow depends on the resistance created by ductwork. This resistance, known as static pressure (SP), is measured in inches of water.

For technical drawings and 3-D models, click on a part number.

Fans
						Overall									Mounting Bases
	Blade Dia.	Airflow @ Static Pressure	Volume	Motor Speed, rpm	Power, hp	Dia.	Ht.	Base Wd.	Wt., lbs.	Max. Ambient Temperature	Housing Material	Specifications Met		Each		Each
Totally Enclosed Motor Enclosure
120V AC, Single Phase—Hardwire
1	10"	60 cfm @ 1/2 in. of H₂O 500 cfm @ 0 in. of H₂O	Not Rated	1,500	1/30	18 5/16"	11 1/4"	19"	21	Not Rated	Aluminum	ETL Listed	0000000	0000000	0000000	0000000
1	12"	430 cfm @ 1/2 in. of H₂O 830 cfm @ 0 in. of H₂O	Not Rated	1,500	1/10	20 5/16"	11 3/4"	19"	30	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
1	14"	520 cfm @ 1/2 in. of H₂O 1,100 cfm @ 0 in. of H₂O	Not Rated	1,100	1/6	27 5/16"	14 5/8"	21"	39	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
1	18"	1,200 cfm @ 1/2 in. of H₂O 2,400 cfm @ 0 in. of H₂O	Not Rated	1,100	1/3	33 9/16"	16 3/8"	26"	60	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
Open Dripproof Motor Enclosure
120V AC, Single Phase—Hardwire
2	11"	600 cfm @ 1/2 in. of H₂O 800 cfm @ 0 in. of H₂O	57 dBA @ 5 ft.	1,625	3/16	23 3/4"	16 1/4"	19"	37	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
2	12"	950 cfm @ 1/2 in. of H₂O 1,250 cfm @ 0 in. of H₂O	62 dBA @ 5 ft.	1,625	1/4	26 1/4"	19 1/8"	21"	53	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
2	14"	2,100 cfm @ 0 in. of H₂O 1,800 cfm @ 1/2 in. of H₂O	66 dBA @ 5 ft.	1,625	1/2	29 3/4"	21 3/4"	21"	56	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000

Belt-Drive Downdraft Roof-Mount Exhaust Fans

Belt-drive fans are quieter and have a longer life span than direct-drive fans because components can be replaced if worn or damaged. More economical than upblast roof-mount exhaust fans, these draw stagnant and humid air out through your roof and then direct it back toward the roof.

Note: Airflow depends on the resistance created by ductwork. This resistance, known as static pressure (SP), is measured in inches of water.

Fans
					Overall						Mounting Bases
Blade Dia.	Airflow @ Static Pressure	Volume	Motor Speed, rpm	Power, hp	Dia.	Ht.	Base Wd.	Housing Material		Each		Each
Open Dripproof Motor Enclosure
120/208-230V AC, Single Phase—Hardwire
16"	2,800 cfm @ 1/2 in. of H₂O 3,200 cfm @ 0 in. of H₂O	70 dBA @ 5 ft.	1,145	3/4	33 11/16"	29 1/4"	26"	Aluminum	0000000	000000000	0000000	0000000
20"	4,900 cfm @ 1/2 in. of H₂O 5,400 cfm @ 0 in. of H₂O	74 dBA @ 5 ft.	1,080	1 1/2	38 1/4"	31 3/4"	30"	Aluminum	0000000	00000000	0000000	000000
208-230/460V AC, Three Phase—Hardwire
24"	6,900 cfm @ 1/2 in. of H₂O 7,750 cfm @ 0 in. of H₂O	73 dBA @ 5 ft.	875	2	44 1/4"	39 11/16"	33"	Aluminum	0000000	00000000	0000000	000000

Direct-Drive Upblast Roof-Mount Exhaust Fans

Direct-drive fans have fewer moving parts than belt-drive fans for less maintenance. These exhaust fans draw stagnant and humid air out through your roof and then expel it up and away from the roof surface. All fans have a disconnect switch to turn off the power for servicing.

Note: Airflow depends on the resistance created by ductwork. This resistance, known as static pressure (SP), is measured in inches of water.

Fans
						Overall									Mounting Bases
	Blade Dia.	Airflow @ Static Pressure	Volume	Motor Speed, rpm	Power, hp	Dia.	Ht.	Base Wd.	Wt., lbs.	Max. Ambient Temperature	Housing Material	Specifications Met		Each		Each
Open Dripproof Motor Enclosure
120V AC, Single Phase—Hardwire
1	11"	400 cfm @ 1/2 in. of H₂O 710 cfm @ 0 in. of H₂O	60 dBA @ 5 ft.	1,625	3/16	22"	18"	19"	43	300° F	Aluminum	ETL Listed	0000000	0000000	0000000	0000000
1	12"	1,100 cfm @ 1/2 in. of H₂O 1,300 cfm @ 0 in. of H₂O	68 dBA @ 5 ft.	1,625	1/3	25 1/2"	25 1/4"	21"	50	300° F	Aluminum	ETL Listed	0000000	000000	0000000	000000
1	16"	2,450 cfm @ 1/2 in. of H₂O 2,900 cfm @ 0 in. of H₂O	69 dBA @ 5 ft.	1,625	3/4	31 7/8"	30 1/2"	24 3/4"	80	300° F	Aluminum	ETL Listed	0000000	00000000	0000000	000000
Totally Enclosed Motor Enclosure
460V AC, Three Phase—Hardwire
2	24"	7,400 cfm @ 0 in. of H₂O	66 dBA @ 15 ft.	1,750	3/4	30"	20 3/4"	36"	208	122° F	Steel	__	0000000	00000000	0000000	000000
2	30"	7,300 cfm @ 1/2 in. of H₂O 11,700 cfm @ 0 in. of H₂O	66 dBA @ 15 ft.	1,150	2	36"	23 1/2"	42"	340	122° F	Steel	__	0000000	00000000	0000000	000000
2	36"	14,800 cfm @ 0 in. of H₂O	68 dBA @ 15 ft.	1,150	1	44"	26 3/4"	48"	370	122° F	Steel	__	0000000	00000000	0000000	000000
2	42"	17,000 cfm @ 1/2 in. of H₂O 24,700 cfm @ 0 in. of H₂O	75 dBA @ 15 ft.	1,150	3	50"	29 1/2"	54"	471	122° F	Steel	__	0000000	00000000	0000000	000000
2	48"	25,500 cfm @ 1/2 in. of H₂O 34,300 cfm @ 0 in. of H₂O	76 dBA @ 15 ft.	1,150	5	56"	38 3/4"	60"	650	122° F	Steel	__	0000000	00000000	0000000	000000

Belt-Drive Upblast Roof-Mount Exhaust Fans

Belt-drive fans are quieter and have a longer life span than direct-drive fans because components can be replaced if worn or damaged. These exhaust fans draw stagnant and humid air out through your roof and then expel it up and away from the roof surface. All fans have a disconnect switch to turn off the power for servicing. Fans are AMCA (Air Movement and Control Association) rated.

Note: Airflow depends on the resistance created by ductwork. This resistance, known as static pressure (SP), is measured in inches of water.

Fans
					Overall								Mounting Bases
Blade Dia.	Airflow @ Static Pressure	Volume	Motor Speed, rpm	Power, hp	Dia.	Ht.	Base Wd.	Max. Temp., °F	Housing Material	Specifications Met		Each		Each
Open Dripproof Motor Enclosure
120/208-230V AC, Single Phase—Hardwire
19"	3,000 cfm @ 1/2 in. of H₂O 3,725 cfm @ 0 in. of H₂O	65 dBA @ 5 ft.	1,725	3/4	39 3/8"	33 3/4"	28"	300°	Aluminum	AMCA Rated, ETL Listed	0000000	000000000	0000000	0000000
208-230/460V AC, Three Phase—Hardwire
24"	4,900 cfm @ 1/2 in. of H₂O 6,250 cfm @ 0 in. of H₂O	67 dBA @ 5 ft.	1,700	1 1/2	43 3/8"	37 1/2"	33"	300°	Aluminum	AMCA Rated, ETL Listed	0000000	00000000	0000000	000000

Wind-Driven Roof-Mount Exhaust Fans

Designed to spin freely with the slightest breeze, these fans create a vacuum that draws air out from buildings and ventilation systems—no electricity required. They are also known as turbine ventilators. Mount fans on your roof away from wind obstructions.

Optional mounting bases are sold separately.

					Galvanized Steel		Stainless Steel
Base Dia.	Overall Ht.	Airflow	Thick.	Max. Temp., °F		Each		Each
6"	14 1/2"	110 cfm @ 4 mph	0.018"	150°	0000000	0000000	0000000	0000000
8"	15 1/2"	195 cfm @ 4 mph	0.018"	150°	0000000	000000	0000000	000000
10"	16 3/4"	305 cfm @ 4 mph	0.018"	150°	0000000	000000	0000000	000000
12"	17 1/4"	440 cfm @ 4 mph	0.024"	150°	0000000	000000	0000000	000000
14"	20"	600 cfm @ 4 mph	0.024"	150°	0000000	000000	0000000	000000
16"	22 1/2"	790 cfm @ 4 mph	0.024"	150°	0000000	000000	0000000	000000
18"	24"	1,000 cfm @ 4 mph	0.024"	150°	0000000	000000	0000000	000000
20"	24 1/2"	1,200 cfm @ 4 mph	0.024"	150°	0000000	000000	0000000	000000
24"	29 1/2"	1,700 cfm @ 4 mph	0.024"	150°	0000000	000000	0000000	000000
30"	32"	2,700 cfm @ 4 mph	0.03"	150°	0000000	000000	0000000	00000000
36"	38"	4,000 cfm @ 4 mph	0.03"	150°	0000000	000000	000000	00

Optional Mounting Bases

Flat Base

Straight Base

Slope Base

All bases have a square bottom, round top, and flashing to simplify installation.

To Order: For slope bases, please specify pitch: 1/12-11/12 in increments of 1/12. To determine pitch, use an angle indicator or divide rise by run (see illustration). For instance, if your roof rises 5" in 12" of horizontal space, your pitch is 5/12.

					Flat Bases		Straight Bases		Slope Bases
Outlet Dia.	Base Wd.	Ht.	Flashing Wd.	Material		Each		Each		Each
8"	10"	10"	4"	Galvanized Steel	0000000	000000	0000000	000000	0000000	0000000
10"	12"	10"	4"	Galvanized Steel	0000000	00000	0000000	00000	0000000	000000
12"	14"	10"	4"	Galvanized Steel	0000000	00000	0000000	00000	0000000	000000
14"	16"	10"	4"	Galvanized Steel	0000000	000000	0000000	000000	0000000	000000
16"	18"	10"	4"	Galvanized Steel	0000000	000000	0000000	000000	0000000	000000
18"	22"	10"	4"	Galvanized Steel	0000000	000000	0000000	000000	0000000	000000
20"	24"	10"	4"	Galvanized Steel	0000000	000000	0000000	000000	0000000	000000
24"	30"	12"	4"	Galvanized Steel	0000000	000000	0000000	000000	0000000	000000