Excellent acoustic and thermal characteristics make for quiet, efficient air delivery. Unwanted “booms” and “cracks” caused by sheet metal ducts, minimized. Made with a foil-scrim-kraft (FSK) vapor retarder and a lightweight, non-woven black mat on the airstream surface.

Applications

Certifications
Product Features
Proven Performance
Delivers high thermal and acoustical performance. Helps maintain temperatures and reduce noise generated by air turbulence and mechanical equipment.
Versatile Fabrication
Simple, streamlined fabrication — done in shop or on the job site. Multiple sizes, minimal capital requirements and only one trade is required to fabricate and install.
Quality Design
Purposefully designed for areas where good temperature control are required. Made with a dark black glass mat facing on the airstream surface enabling a clean cut.
Product Details
Technical Data
Technical Data
Property (Unit) Test Performance
Maximum Service Temperature ASTM C411 250° F (121° C)
Water Vapor Permenance  ASTM E96 0.02 perms or less
Water Vapor Sorption (by weight) ASTM C1104 Less than 5%
Flexural Rigidity NAIMA AHS-100-74 Available in 2 stiffness values: El-475 and El-800; Flexural rigidity (El) is the product of Young's modulus of elasticity (E) and moment of inertia (l)
Air Velocity UL 181 Maximum 5,000 ft./min. (1,524 m/min.)
Tested to 12,500 ft./min. (3,810 m/min.)
Internal Static Pressure UL 181 Maximum +2" water (498 pascals [Pa])
Microbial Growth ASTM G21, UL 181 Pass, does not support the growth of fungi or bacteria
Surface Burning Characteristics (flame spread/smoke developed)  ASTM E84, UL 723, CAN/ULC S102 25/50, UL/ULC listed
 
Forms Available
Forms Available
Type Size* Edge Pieces/Carton**
EI-475 1" (25 mm) 48" x 96" (1219 mm x 2438 mm) Shiplap 8
EI-800 48" x 120" (1219 mm x 3048 mm) Butt, Shiplap 6
EI-800 1.5" (38 mm) Shiplap 4
2" (51 mm) Butt, Shiplap 3

*Other lengths available on custom order basis.
**Palletized packaging available on request.
Thermal Resistance R and Conductivity k
Thermal Resistance R | ASTM C518 
Mean Temperature 75° F (24° C)
Thickness R-Value (R.S.I)
1" (25 mm) 4.3 (0.76)
1.5" (38 mm) 6.5 (1.14)
2" (51 mm) 8.7 (1.53)
“R” Units ft2 ∙  hr  ∙ ˚F BTU (m2 ∙ ˚C W)
 
Thermal Conductivity k | ASTM C177
Mean Temperature 75° F (24° C)
  k-Value
EI-475 and EI-800 0.23 (.033)
“k” Units BTU ∙ in ft2 ∙  hr  ∙ ˚F W m2 ∙ ˚C)
Sound Absorption Coefficients
Sound Absorption Coefficients | ASTM C423, Type A Mounting
Octave Band Center Frequency (Cycles/Sec.)
Thickness 125 250 500 1000 2000 4000 NRC
1" (25 mm) 0.03 0.25 0.62 0.92 1.03 0.97 0.70
1.5" (38 mm) 0.02 0.44 0.96 1.17 1.16 1.12 0.95
2" (51 mm) 0.19 0.64 1.08 1.13 1.06 1.06 1.00
Friction Loss & Recommended Duct Dimensions Without Reinforcement
Friction Loss | Inches of Water Per 100'
Ft./min. Hydraulic Diameter
Velocity 10" 16" 24" 32" 40" 72" 100"
500 0.056 0.031 0.018 0.013 0.010 0.005 0.003
600 0.080 0.044 0.026 0.018 0.014 0.007 0.004
700 0.108 0.059 0.035 0.025 0.019 0.009 0.006
800 0.140 0.077 0.046 0.032 0.024 0.012 0.008
900 0.176 0.096 0.058 0.040 0.031 0.015 0.010
1000 0.216 0.118 0.071 0.050 0.038 0.018 0.012
2000 0.845 0.463 0.278 0.194 0.147 0.071 0.048
3000 1.887 1.034 0.620 0.432 0.328 0.159 0.106
4000 3.340 1.831 1.097 0.765 0.580 0.281 0.188
5000 5.206 2.854 1.710 1.193 0.904 0.438 0.293
 
Recommended Maximum Duct Dimensions Without Reinforcement*
Internal Pressure
Inches of Water
EI-475-1" EI-800-1"
0.5 (125) 1.0 (249) 2.0 (498) 0.5 (125) 1.0 (249) 2.0 (498)
Positive 36" (914 mm) 24" (610 mm) 15" (381 mm) 36" (914 mm) 24" (610 mm) 18" (457 mm)
Negative 30" (762 mm) 24" (610 mm) 15" (381 mm) 30" (762 mm) 24" (610 mm) 18" (457 mm)

*This table summarizes span/pressure limitations for unreinforced duct. For larger ducts, refer to NAIMA’s “Fibrous Glass Duct Construction Standard,” or Knauf Insulation's Air Duct Fabrication Manual.
(Pressure—Pascals [Pa])
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