SDB Belt Drive Centrifugal Downblast Roof Exhaust Fan

Centrifugal Roof & Wall Fan Series

SDB Model
SDB Model

High Wind Tie-Down Kit Option Available

Model Features

  • Exhaust air up to 31,563 CFM in high static pressure applications up to 1-3/4" w.g.
  • Attractive spun aluminum exterior
  • Belt drives permit easy performance adjustments when needed
  • Curved non-overloading backward inclined wheel for efficiency at higher static pressures
  • AMCA Air and Sound Licensed
  • cULus 705 Listed
  • Miami-Dade NOA and Florida Product Approval Option Available Download letter here.
  • Listed with the Texas Department of Insurance under Product Evaluation RV-126 for wind load and windborne debris resistance per IRC/IBC 2018
  • This product meets the requirements of Buy American (2009) and Build America, Buy America (BABA), as part of IIJA (2022). Download letter here.

AMCA Air and SoundcULusMiami-Dade Approved   BABA-ACT

Model Overview

The SDB belt drive fans are designed to exhaust air up to 31,563 CFM in high static pressure applications up to 1-3/4". The aluminum exterior provides an attractive appearance. Belt drive results in lower operating RPM and sound levels, making the Model SDB well suited to applications where quiet operation is important. Belt drive also permits easy performance adjustments when needed to balance the total ventilation system. The non-overloading backward inclined wheel with its higher static pressure capability makes this unit suitable for either ducted or non-ducted applications. Its roof mounting permits location near the area to be ventilated, allowing short duct runs and more efficient operation.

SDBs are primarily used for the exhaust of relatively clean air from a wide range of commercial, industrial and institutional environments such as manufacturing and assembly plants, office buildings, schools, hospitals, restaurants, athletic facilities and many others.

5-year fan housing warranty, 1-year motor warranty

Size CFM Range Max SP
6 41 to 375 7/8"
7 44 to 547 7/8"
8 194 to 1,132 1"
10 244 to 1,422 1"
12 425 to 1,870 1-1/4"
14 802 to 3,525 1-1/2"
15 543 to 3,724 1-1/2"
16 1,275 to 4,135 1-1/2"
18 1,389 to 5,787 1-3/4"
20 1,728 to 6,259 1-3/4"
22 2,522 to 8,098 1"
24 2,503 to 9,287 1-1/4"
27 3,856 to 10,169 1"
30 4,336 to 15,782 1-1/2"
33 4,025 to 17,165 1-1/4"
36 6,385 to 19,560 1-1/4"
42 8,256 to 25,590 1-1/2"
48 10,456 to 31,563 1-1/4"
Dimensional Drawing for the SDB Model

Dimensional data is displayed in inches.

Size A B C D Roof Opening Curb O.D. Damper O.D.
6 18 30-1/8 25 3-3/8 13-1/2 16-1/2 12
7 18 30-1/8 25 3-3/8 13-1/2 16-1/2 12
8 18 30-1/8 25 3-3/8 13-1/2 16-1/2 12
10 18 30-1/8 25 3-3/8 13-1/2 16-1/2 12
12 20 31-11/16 27-5/8 3-7/8 15-1/2 18-1/2 14
14 20 31-11/16 27-5/8 3-7/8 15-1/2 18-1/2 14
15 24 32-1/2 32-7/8 4 19-1/2 22-1/2 18
16 24 32-1/2 32-7/8 4 19-1/2 22-1/2 18
18 30 36-3/8 39-3/16 4-5/8 25-1/2 28-1/2 24
20 30 38-5/16 45 6-1/8 25-1/2 28-1/2 24
22 30 38-5/16 45 6-1/8 25-1/2 28-1/2 24
24 36 46-5/8 49-3/8 6 31-1/2 34-1/2 30
27 36 49-1/16 49-3/8 8-1/2 31-1/2 34-1/2 30
30 42 50-1/4 56 7-3/8 37-1/2 40-1/2 36
33 42 50-1/4 56 7-3/8 37-1/2 40-1/2 36
36 42-5/16 48-7/8 64-1/4 7 37-1/2 40-1/2 36
42 54-1/4 54-7/8 71-3/16 11-1/2 49-1/2 52-1/2 48
48 54-1/4 58-1/8 78-3/16 12-7/8 49-1/2 52-1/2 48

SDB Kits

Select S-Series (Centrifugal Roof Fans) models are now hurricane and high wind certified for wind-borne debris impact resistance and wind load design pressures up to ±150 PSF.

SDB Tie Down Kit

High Wind Tie-Down Kit

  • Tie-downs
  • Fastened motor cover
  • Reinforced birdscreen

Additional accessories are available for certain products. Contact your S&P Representative for more information about these accessories.

Standard Accessories

Automatic Belt Tensioner    
Automatic (Gravity) Damper    
Backdraft Damper Submittal  
Curb Cap Adaptor Submittal  
Curb Hinge Arrangement    
Ecowatt® Drive Submittal Flyer
Motor Operated Damper    
Roof Curb Submittal  
Self-Flashing Curb Submittal  
Ventilation Gas Detectors Submittal IOM

Miami Dade Certification PreviewDownload
Product Line Overview Preview Download
Centrifugal Roof and Sidewall Catalog Preview Download
Typical Specification Sheet PreviewDownload
Submittal PreviewDownload
IOM PreviewDownload

SDB Download

  • Bathrooms
  • Dormitories
  • Garages
  • General/Clean Air
  • General (non-grease) Kitchen Areas
  • Manufacturing and Assembly Plants
  • Offices
  • Places of Worship
  • Schools
  • Spark Resistant
  • Warehouses