BGH Fabricated Gravity Relief/Intake Ventilator

Gravity Vents

BGH Model

Model Features

  • Exhaust or Supply air up to 90,000 CFM in static pressure applications up to 1/4" w.g.
  • All aluminum or steel construction with standard mill finish.
  • All curb base corners miter cut and continuous welded.
  • Hood reinforced and braced for extra strength.
  • Hood assembled with standing and snap back seams secured with spot welds.
  • Hood perimeter opening area same as throat area.
    • Relief 1:1 ratio
    • Intake 2:1 ratio
  • Birdscreen of 1/2" x 1/2" mesh galvanized welded wire. (NOT AVAILABLE WITH FILTERS)
  • Hood has a wide overhang for storm protection.
  • This product meets the requirements of Buy American (2009) and Build America, Buy America (BABA), as part of IIJA (2022).Download letter here.


Model Overview

BGH Gravity Ventilators offer a modern low silhouette design that blend with roof lines and other equipment. Designed for maximum airflow passage and weathertight integrity, BGH comes in either intake or relief models with aluminum or galvanized finishes. An extensive range of sizes is offered with many standard and optional features. Exhaust models have a 1:1 ratio of hood perimeter opening to throat area and supply models incorporate a 2:1 ratio.

To meet other size or ventilation capacity requirements, custom sized units are available upon request. Consult your representative or factory for specific details and performance capabilities.

Industry best 1-year fan housing warranty

Product Line Overview
General Catalog Section
Typical Specification Sheet
Gravity Ventilator Sizing Guide

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

Standard Accessories

Aluminum Birdscreen    
Hinged Hood    
Insulated Hood    
Insect Screen    
Roof Curb    

  • General/Clean Air