With a labyrinth structure containing thousands of tiny air pockets, apart from having good thermal insulation property, glaswool also has excellent noise absorption characteristics. Being an incombustible material, thus safe from fire hazard, glaswool is widely used in the building industry, particularly for housing projects.

Manufactured under the form of blankets and batts, with bare faces or laminated with aluminium foil on one or both sides, glasswool often has typical sizes as below:

• Blanket:
  *   Width: 1.2m
  *   Length:  7.5m - 15m - 30m
  *   Thickness: 25mm - 50mm - 75mm - 100mm
  
• Batt:
  *  25mm x 0.6m x 1.2m 
  *  50mm x 0.6m x 1.2m 
  *  100mm x 0.6m x 1.2m 
  
• Density:
  *  10kg/m3 - 12kg/m3 - 16kg/m3 (low density)
  *  24kg/m3 - 32kg/m3 - 48kg/m3 (medium density)
  *  64kg/m3 - 96kg/m3 (high density)

For glasswool of the same density, its added R-value is in direct proportion to its thickness. Under laboratory testing conditions (20-24 degree C, 50% relative humidity), bare glaswool of 10kg/m3 50mm thick has an added R-value at approximate 1.15 - 1.20 m².K/w

In reality, for the convenience of storage and transportation, glasswool rolls are often compressed at manufacturing plants for the purpose of volume saving of finished products. Consequently, the actual thickness of glasswool blankets of low density (10kg/m3 - 12kg/m3 - 16kg/m3) is only 70-75% compared to its nominal thickness printed/stated in packaging and brochure. It means the actual added R-value of glasswool of ( __ ) mm sold in the market is about 70-75% its nominal thermal value.