Jet Stream® Ultra Blowing Wool Insulation

Jet Stream® Ultra Blowing Wool Insulation

Knauf Insulation Jet Stream® ULTRA Blowing Wool Insulation is an unbonded, virgin fibrous glass blowing insulation designed with optimal thermal properties and excellent coverage and blowing characteristics.


Knauf Insulation Jet Stream ULTRA Blowing Wool Insulation is installed in open attics of both new and existing structures and/or in closed cavity applications with the BIBS system (Blow-in-Blanket System) in which ventilation is not required. Jet Stream ULTRA, when used in closed cavity applications is BIBS approved and can only be installed by BIBS certified installers to ensure the highest quality installed performance. Loose fill blowing insulation is intended for use where pneumatically installed insulation is most cost-effective.

Features and Benefits

Excellent Thermal Performance

  • Fills all gaps and voids, creating a thermal barrier against outside air and better temperature control
  • Resists heat flow with an R-value of:
    • R-15 in 2 x 4 construction
    • R-23 in 2 x 6 construction


  • One product, one inventory, two applications

Energy Conservation

  • Reduces fuel usage and utility bills for heating and air conditioning


  • Each bag contains the equivalent of over 30 recycled bottles, with a minimum of 60% post-consumer recycled glass content

Noise Reduction

  • Improves Sound Transmission Class (STC) ratings by 4 to 10 points


  • Jet Stream ULTRA Blowing Wool Insulation is a pneumatically installed insulation product (see Equipment Required below).


  • Non-combustible, non-corrosive
  • Will not rot, mildew or deteriorate

Thermal Performance

Jet Stream ULTRA Blowing Wool Insulation provides you a choice of R-values based on the installed thickness and installed weight per square foot. The tables below show the minimum requirements for obtaining the desired R-value.

The stated thermal resistance (R-value) is provided by installing in accordance with the manufacturer‘s instructions: the required number of bags per 1,000 sq. ft. of net area, and at no less than the labeled minimum thickness. Failure to install both the required number of bags and at least the minimum thickness will result in lower insulation R-values.

Field blending of this product with other loose fill insulation or application of this product in conjunction with adhesive or binder systems may affect its thermal performance and is not recommended by the manufacturer.

Specification Compliance

  • ASTM C 764; Type I
  • HH-I-1030B; Class B
  • Greenguard certified by UL Environment
  • Greenguard Gold certified by UL Environment

Knauf Jet Stream ULTRA Blowing Wool Insulation is manufactured with a minimum of 60% post-consumer recycled glass.

Technical Data

Surface Burning Characteristics

  • Does not exceed 25 Flame Spread, 50 Smoke Developed when tested in accordance with ASTM E 84 and CAN 4-S102.2

Critical Radiant Flux (ASTM E 970)

  • Greater than 0.12 W/cm2

Moisture Vapor Sorption (ASTM C 1104)

  • 5% maximum by weight

Corrosion (ASTM C 764)

  • No greater than sterile cotton

Microbial Growth (ASTM C 1338)

  • Does not support microbial growth

Non-Combustibility (ASTM E 136)

  • No temperature rise above 54°F (30°C)

Equipment Required

To achieve labeled R-value, this product must be applied with a pneumatic blowing machine and a corrugated hose with a minimum ¼" internal corrugation, a minimum length of 150' and a diameter of at least 3". Coils in the hose should not be less than 36" in diameter. Acceptable material feed rate is 5-35 lbs./minute. The recommended feed rate is 15-25 lbs./minute. For closed-cavity applications, netting must be applied to properly contain the blown-in insulation.


  • Jet Stream ULTRA Blowing Insulation is packaged in a strong, poly bag that offers excellent protection from abuse, dust and moisture.
  • Knauf Insulation packages are lightweight, stack without slipping, and are easy to handle and store.

Glass Mineral Wool and Mold

Glass mineral wool insulation will not sustain mold growth. However, mold can grow on almost any material when it becomes wet and contaminated. Carefully inspect any insulation that has been exposed to water. If it shows any sign of mold, it must be discarded. If the material is wet, but shows no evidence of mold, it should be dried rapidly and thoroughly. If it shows signs of facing degradation from wetting, it should be replaced.


The chemical and physical properties of Knauf Jet Stream ULTRA Blowing Insulation represent typical average values determined in accordance with accepted test methods.

The data is supplied as technical service and is subject to change without notice. References to numerical flame spread ratings are not intended to reflect hazards presented by these or any other materials under actual fire conditions.

Check with your Knauf Insulation sales representative to assure information is current.