
Submittal Sheet
Fiber Glass Duct Board
❏
TYPE 475, 1" (25mm)
❏
TYPE 800, 1" (25mm)
❏
TYPE 800, 1
❏
TYPE 1400, 2" (51mm)
Description
1
/
2" (38mm)
Owens Corning                 
Fiber Glass Duct Board is a rigid, resin 
bonded fibrous glass board with a tough, 
damage-resistant, flame retardant, 
reinforced aluminum foil (FRK) facing. 
When fabricated into duct systems, it 
combines excellent thermal and 
acoustical insulating properties with 
substantially airtight transmission of air 
when all joints are sealed with UL 181A 
listed closures.
              Fiber Glass Duct Board 
features a durable air stream surface that 
isolates the glass fiber substrate from the 
airstream and inhibits penetration of the 
insulation by dirt, dust and other 
pollutants. This durable air stream surface 
makes it easy to clean the duct system 
using methods and equipment described 
in North American Insulation 
Manufacturers Association (NAIMA) 
Publication AH122, Cleaning Fibrous
Glass Insulated Duct Systems, 
Recommended Practice.
Uses
             Fiber Glass Duct Board 
may be used to fabricate components for 
indoor commercial and residential 
heating, ventilating and air conditioning 
duct systems operating at static pressures 
to ±2 in. w.g. (500 Pa), internal air 
temperatures 40°F (4°C) to 250°F 
(121°C), and air velocities to 6,000 fpm 
(30.5 m/s). Straight duct sections, elbows, 
tees, offsets and other system elements 
can quickly and easily be fabricated and 
assembled into a complete air 
transmission system using these 
lightweight, thermally efficient boards.
Features and Benefits
Bacterial and Fungal Growth Resistance
A durable air stream surface includes an 
EPA registered biocide that protects the 
air stream surface from microbial growth 
and meets requirements of ASTM C 1338, 
ASTM G 21 (fungi test) and ASTM G 22 
(bacteria test).
Tips to Avoid Mold Growth in Ducts
Mold in duct systems occurs when 
moisture comes into contact with dirt 
or dust collected on the duct system 
surfaces. Proper filters will minimize 
the collection of dust and dirt, but 
care needs to be exercised to prevent 
water formation in the duct. A 
properly sized and operated air 
conditioning unit will minimize the 
likelihood of water formation. The 
system must be maintained and 
operated to insure that sufficient 
dehumidification is occurring and that 
filters are installed and changed as 
recommended by the equipment 
manufacturer.
Assured Thermal Performance
R-values as published for 
              Fiber Glass Duct Board 
are superior to those of compressible 
insulation of equal thickness. Factory 
control of thickness assures that installed 
R-values will be as published for the 
product.
Acoustically Efficient
Duct systems built with these boards 
absorb fan and air turbulence noise; 
reduce popping noises caused by 
expansion, contraction and vibration. 
Fabrication and installation are quieter.
Single Contractor Accountability
Thermal/acoustical insulation board plus 
jacket forms a single component duct 
system, thus reducing inspection time.
Lightweight
These lightweight boards are easier to 
transport and handle than insulated sheet 
metal ducts. They reduce the load 
imposed on the structure by the duct 
system.
Virtually Eliminates Air Leakage
Closures with UL 181A listed pressuresensitive tape, heat-activated tape, or 
glass fabric and mastic virtually eliminate 
air leakage. This saves energy and 
removes the need for system overdesign.
Code Compliance
Meets the following model codes and 
most other applicable codes: NFPA 
90A/90B, ICC International Mechanical 
Code, SBCCI, ICBO, BOCA, CABO, Corps 
of Engineers Guide Spec., NYC MEA 
#186-69.
Supported by Industry Standards
Proper fabrication and installation guidelines help ensure long-term performance 
of the system. These standards, 
developed by NAIMA and SMACNA, lead 
to clearer understanding between 
specifier and contractor.
Physical Property Data
Property Test Method Value
Maximum operating temperature limits  UL 181 Internal: 250°F (121°C)
Maximum air velocity UL 181 Erosion Test  6,000 fpm (30.5 m/s) 
Static pressure limit UL 181 ±2 in. w.g. (500 Pa) 
Water vapor sorption ASTM C 1104 <3% by weight at 120°F (49°C), 95% R.H. 
Mold growth UL 181 Meets requirements
Fungi resistance ASTM G 21 Meets requirements 
Bacteria resistance ASTM G 22 Meets requirements
Surface burning characteristics UL 723* Flame spread 25*
Fire retardancy UL 181 Flame penetration: 30 min.
* The surface burning characteristics of these products have been determined in accordance with UL 723. This standard should be
used to measure and describe the properties of materials, products or assemblies in response to heat and flame under controlled 
laboratory conditions and should not be used to describe or appraise the fire hazard or fire risk of materials, products or assemblies 
under actual fire conditions. However, results of this test may be used as elements of a fire risk assessment which takes into account 
all of the factors which are pertinent to an assessment of the fire hazard of a particular end use. Values are reported to the nearest 
5 rating.
External: 150°F (66°C)
Smoke developed 50

Fiber Glass Duct Board
Availability
                Fiber Glass Duct Board
Acoustical Performance
Sound absorption coefficients at octave band center frequencies, Hz.
is available in the following forms:
TYPE 475, 1" (25mm) thick 
TYPE 800, 1" (25mm) thick
1
/
TYPE 800, 1
TYPE 1400, 2" (51mm) thick
Type designates board stiffness defined by flexural rigidity. 
Type selection depends on duct size, pressure and reinforcement 
schedule. The 1 
superior thermal value.
2
" (38mm) thick
1
/
2" (38mm) and 2" (51mm) thickness provides
UL Class 1 Air Duct
National Fire Protection Association 
Standards NFPA 90A and 90B for air 
conditioning and ventilating systems 
require air ducts to be Class 0 or 1. The 
tests set stringent requirements on fire 
safety as well as ruggedness. To meet 
Class 1 air duct requirements, the system 
must withstand UL 181 tests such as 
rupture, pressure loss, impact, collapse, 
puncture, static load and fire retardancy 
(30 minute flame penetration test). Also, 
to qualify as a Class 1 Air Duct System, 
the following UL 723 fire testing 
requirements must be met: Flame spread, 
25; Smoke developed, 50.
Limitations
Fiber glass ducts should not be used in 
the following applications:
A. Kitchen or fume exhaust ducts, or to
convey solids or corrosive gases;
B. In concrete or buried below grade; 
C. Outdoors; 
D. As casings and/or housings of built-up
equipment;
E. Immediately adjacent to high
temperature electric heating coils without 
radiation protection;
F. For vertical risers in air duct systems
serving more than two stories in height;
G.With coal or wood fueled equipment,
or with equipment of any type which 
does not include automatic maximum 
temperature controls;
H. In variable air volume systems on the
high pressure side unless reinforced to 
withstand the full fan pressure;
I. As penetrations in construction where
fire dampers are required, unless the fire 
damper is installed in a sheet metal sleeve 
extending through the fire wall; or
Type 475, 1" (25mm) 0.08 0.19 0.69 0.94 0.99 0.98 0.70 
Type 800, 1" (25mm) 0.08 0.19 0.69 0.94 0.99 0.98 0.70
1
Type 800, 1 
Type 1400, 2" (51mm) 0.14 0.72 1.15 1.12 1.06 1.07 1.00
These data were collected using a limited sample size and are not absolute values. Therefore, reasonable tolerances must be 
applied. Tests were conducted in accordance with ASTM C 423, Mounting A (material placed against a solid backing).
/
Thermal Performance, at 75°F (24°C) Mean Temperature
R-value, hr•ft2•°F/Btu (RSI, m2•°C/W) 4.3 (0.76) 6.5 (1.15) 8.7 (1.53) 
k-value, Btu•in/hr•ft 
C-value, Btu/hr•ft
Mean temperature is the average of two temperatures: that of the air inside the duct and that of the ambient air outside it. 
Note: Specified design thickness should be adequate to prevent exterior surface condensation.
J. When the duct system is located in
non-conditioned space and is used for 
cooling only (when heating is from 
another source), unless all registers which 
would allow moist air into the duct system 
are vapor sealed during the heating 
season to prevent condensation from 
forming inside the duct.
Application Recommendations
Fabrication and installation of fiber glass 
Duct Systems shall be in accordance with 
the UL listing and shall conform to Owens 
Corning’s published methods and/or latest 
editions of NAIMA (North American 
Insulation Manufacturers Association)
Fibrous Glass Duct Construction 
Standards or SMACNA (Sheet Metal
and Air Conditioning Contractors 
National Association) Fibrous Glass 
Duct Construction Standards. One of 
the following closure methods must be 
employed to meet the requirements of 
UL 181. USE OF A NON-LISTED 
CLOSURE SYSTEM VOIDS THE UL 
CLASS 1 AIR DUCT RATING.
1. Pressure-Sensitive Tape
Any tape listed and labeled under 
UL 181A, Part I (P).
a. All longitudinal and circumferential
joints must be stapled with outward 
1
flaring 
/
2
(50mm) (approx.) O.C.
b. Wipe surface where tape is to be 
applied to field joints with clean cloth. 
If surface has grease or oil, saturate 
cloth with approved solvent. Refer to 
tape manufacturer’s recommendations.
c. Center tape over edge of stapling 
flap and rub firmly in place 
immediately after application, using 
a squeegee or similar tool.
d. A heat sealing iron must be used 
to assure a good bond when installed
OWENS CORNING WORLD HEADQUARTERS
ONE OWENS CORNING PARKWAY 
TOLEDO, OHIO, USA 43659
1-800-GET-PINK 
www.owenscorning.com
EnDuraGold™ is a trademark of Owens Corning. 
Pub. No. 57577  Printed in U.S.A., November 2002   Copyright © 2002 Owens Corning
below 50°F (10°C).
e. Tape should not be applied to 
surface of duct board when 
temperature is below 32°F (0°C) 
due to the possibility of entrapping 
125 250 500 1000 2000 4000 NRC
2" (38mm) 0.12 0.33 0.92 1.04 1.03 1.02 0.85
1
1" (25mm) 1
2
•°F (  , W/m•°C) 0.23 (0.033) 0.23 (0.033) 0.23 (0.033)
2
•°F (W/m2•°C) 0.23 (1.32) 0.16 (0.87) 0.12 (0.65)
/
2" (38mm) 2" (51mm)
ice crystals which will cause tape 
to loosen upon melting. Heat surface 
first to drive off moisture.
2. Heat-Activated Tape
Any tape listed and labeled under 
UL 181A,Part II (H).
a. All longitudinal and circumferential
joints must be stapled with outward 
1
flaring 
/
"(13mm) (min.) staples, 2" 
2
(50mm) (approx.) O.C.
b. Wipe surface where tape is to be 
applied with clean cloth. If surface 
has grease or oil, saturate cloth with 
approved solvent. Refer to tape 
manufacturer’s recommendations.
c. Center tape over joint and seal 
down tape end with 500°F (260°C) 
iron. Do not use heat gun; heat and 
pressure are both required to effect 
a seal.
d. Press down entire length of tape 
to hold in place using a smearing 
action to get good bond. Colored 
dots on tape surface darken when 
satisfactory bonding temperature 
is reached.
e. Staples may be omitted when 
automatic closure machines such 
as Glass Master Closemasters are 
used. Iron temperature must be set 
at 650°F (343°C) minimum. 
" (13mm) (min.) staples, 2"
Continuous production may require 
periodic pauses to allow sealing iron 
to recover to 650°F (343°C).
f. Allow joint to cool before 
stressing.
3. Mastic and Glass Fabric
Any mastic and glass fabric closure 
system listed and labeled under UL 
181, Part III (M).
a. All longitudinal and circumferential
joints must be stapled with outward
1
flaring 
/
"(13mm) (min.) staples, 2"
2
(50mm) (approx.) O.C.
b. Brush mastic onto joint and embed
glass fabric in mastic.
c. Brush second coat of mastic over 
fabric until completely filled.
d. Allow joints to dry in accordance 
with mastic manufacturer’s 
recommendation before pressurizing 
system.