Quantity and positioning of hangers

Extract from SMACNA Standard for fastener spacing
    
  FLEXIBLE DUCT LINER FASTENER SPACING


MAXIMUM SPACING FOR FASTENERS USED WITH FLEXIBLE DUCT LINER
Velocity Upstream Edge Mid-Section
A B C D E F
0 - 2000 FPM 3" 12" 12" 6" 18" 12"
2001  -  4000 FPM 3" 6" 6" 6" 16" 12"
4001  -  6000 FPM 3" 6" 6" 6" 16" 12"
  RIGID DUCT LINER FASTENER SPACING


MAXIMUM SPACING FOR FASTENERS USED WITH RIGID DUCT LINER
Velocity Upstream Edge Mid-Section
A B C D E F
0 - 2000 FPM 3" 15" 15" 15" 15" 15"
2001  -  4000 FPM 3" 15" 15" 15" 15" 15"
4001  -  6000 FPM 3" 12" 12" 12" 12" 12"
Specific recommendations for self-adhesive hangers
 
Insulation material Recommended quantity of hangers per square metre
Density Thickness Temp. 23°C Temp. 40°C Temp. 60°C Temp.80°C
20 kg
per cubic metre		 25mm
50mm
100mm		 4
4
4		 4
4
4		 4
4
4		 4
4
4
40 kg
per cubic metre		 25mm
50mm
100mm		 4
4
4		 4
4
4		 4
4
6		 4
6
8
80 kg
per cubic metre		 25mm
50mm
100mm		 4
4
4		 4
4
6		 4
6
8		 6
8
16
120 kg
per cubic metre		 25mm
50mm
100mm		 4
5
6		 5
6
8		 6
8
12		 8
12
24
Insulation fasteners : Choice of system