Eclipse® Air Duct Board

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.

Eclipse^® Air Duct Board will be replaced by Performance+ Air Duct Board after Dec. 31, 2024.

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 Permeance	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	1" (25 mm)	48" x 120" (1219 mm x 3048 mm)	Butt, Shiplap	6
EI-800	1.5" (38 mm)		Shiplap	4
EI-800	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"
Internal Pressure Inches of Water	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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