Barymat BGM 7-4B consists of a limp, dense, mineral filled plastic barrier which was designed to provide maximum transmission loss for its weight. This layer is laminated to a one inch, semi-rigid fiberglass board which increases performance and provides thermal insulation. An abrasion resistant, clear polyester film protects the barrier layer from dirt, moisture and oily contaminants.
Unit of Measure

Performance Data

N/A Performance data is an extract from NRC - Ottawa report on tests according to ASTM E 90-90 with material adhered to 16 ga. steel.

NOTICE: Stated performance data is based on recognized testing methods. Product performance can be affected by field conditions and installation methods. Users of these products are responsible for determining suitability for their application and compliance with any legal provisions including those relating to health and safety.

Applications and Product Data


  • Engine Compartment Liner
  • Thermal Acoustic Decoupler
BARYMAT BGM 7-4B is easy to apply and can be cut with common utility knives. For secure and permanent installations use mechanical fasteners or specified adhesives - available from Firwin Corp.


N/A Approx. 1.25 in. - overall composite thickness

Standard Dimensions

N/A Sheets: 48"wide X 72", untrimmed (24 sq.ft.)

Typical Physical Properties

Thermal Conductivity of Foam at 75°F (24°C)

N/A ASTM C 518 - 0.24 Btu. in. / hr. ft.² ºF , 0.034 W/mºC

Barrier Colour

N/A Black

Composite Weight

N/A 26 oz. per sq. ft.

Fiberglass Color

N/A Yellow

Polyester Film Color

N/A Clear

Transmission Loss


Frequency (Hz) Transmission Loss (dB) BGM 7-4B
80 22
100 20
125 15
160 15
200 22
250 29
315 33
400 37
500 41
630 43
800 46
1000 48
1250 51
1600 52
2000 49
2500 48
3150 53
4000 56
5000 58
6300 59
STC 36