Specification Sheet

457
OPTIONS/ACCESSORIES
Aluminum Birdscreens: Consists of .060” thick 1/2” x 1” diamond shape expanded aluminum. Attached
to the full perimeter opening of the hood with stainless or zinc plated fasteners.
Hinged Hood: For easy access to backdraft dampers and to service lters and screens.
Insulated Hood: To reduce condensation drip. Offered in rubberized anti-condensate undercoating or
as 1” thick berglass insulation.
Filters: Offered as 1” or 2” thick permanent type aluminum mesh mounted for easy cleaning and
attached to full perimeter opening of the hood. Birdscreens are omitted when equipped with lters.
Note: Add .17” to the area listed in the tables when using lters on AIR INTAKE ventilators.
Insect Screen: Consists or 18 mesh aluminum screen. Attached to the full perimeter opening of the
hood. Note: When using insect screens on EXHAUST ventilators add .10” to the area listed in the
tables. For INTAKE ventilators add .05” to the listed area.
Roof Curb: Prefabricated heavy-gauge galvanized steel, welded construction, 12” high
(other heights are also available) with 1-1/2” wood nailer. Assures perfect t of to roof
opening. Options include burglar bars, single or double pitch construction and hinged
curbs for easy duct access.
Special Coatings: for protective and decorative purposes. Available coatings include: Synthetic
Resin, Epoxy, and Heresite (air-dried phenolic). Contact your representative or the factory for more
information on available coatings and colors.
MODEL BGH
FABRICATED GRAVITY RELIEF/INTAKE VENTILATORS