29 Guage galvalume steel ducts
Lengths up to 20' 3"
Standard length is 40 5/8"
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Trunk lines
Perimeter dimensions above 38 5/8" will require a 2
piece
duct
Standard = 6"x14"x405/8"
Max dimensions = 68" (34" per piece)
Examples: 12"x22" 10"x24"
18"x16"
Walls over 14" will require support ribs
2 per section or 36" o/c whichever is more
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Massive Trunk lines:
Perimeter dimensions above 68" will require a 4 piece
duct
Will require support ribs at 24" o/c |
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http://durableduct.com/designs/duct-1.jpg |
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