Installation Guide
Ventamatic, Ltd. | 100 Washington Ave, Mineral Wells, TX 76068 ▪ Phone: (800) 433-1626 ▪ www.bvc.com 
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Deciding on a Joist-In or Joist-Out Installation 
Joist-In Installation 
The ceiling joists will be left intact for this 
method. You will need another attic access, as the 
fan will not fit through the shutter opening with 
the joist(s) in place. 
Joist-Out Installation 
This method involves removing one or more 
ceiling joists. This is the preferred method, as the 
best location does not necessarily coincide with 
the position of the joists.
Step 1: Prepare the Shutter Opening
  Find a spot in the center of the hallway, drill a hole 
and feed a wire through to mark it. 
  Mark space around the wire equal to the area of the 
rough shutter opening in the chart below in the joist-
in or joist-out option below. 
  Remove all insulation above the installation site. 
Joist-In Installation 
  Align shutter vein with ceiling joist in the 
center of the shutter opening. 
  Draw a line on the ceiling marking the rough 
opening size of the shutter frame. 
  Double-check the accuracy of the dimensions 
you have marked and that all the corners are 
square. 
TIP: Use the shutter as a template to outline the 
opening by drawing the cutout line around the 
inside edges. 
Joist-Out Installation 
  Drill two ¼” holes (from attic floor 
through the ceiling) at the two corners that are 
aligned with one of the ceiling joists. 
  On ceiling side, draw a straight line between 
the two drilled holes. Use this line as a guide 
to mark the other three sides of the shutter 
opening, using rough opening dimensions 
chart above. 
  From ceiling side, drill two more ¼” holes at 
the remaining corners. 
Fan Size 
Shutter Rough Opening (L X W) 
24-in. 
28” X 26” 
30-in. 
32 1/4” X 29 1/2” 
36-in. 
34” X 37 1/2” 








