How To Install Inner-Safe Batt Insulation

Adding Inner-Safe batt insulation to interstitial spaces is a quick, easy process. Please review these steps in full before starting installation. If you have questions, contact Knauf Insulation Technical Support.

Recommended Materials and Equipment


Estimate How Many Batts Are Needed

  • The number of square feet of Inner-Safe is marked on its packaging. Calculate the total number of packages of Inner-Safe needed by dividing the total area of the interstitial space by the square footage in one package to find the total number of packages required. Round up to the nearest whole package.
  • Determine the number and width of Inner-Safe batts required to fill the cavity.
    • IMPORTANT NOTE: NFPA 13, Section permits a MAXIMUM AIR GAP OF TWO INCHES at the top of the interstitial space.


Installing Batt Insulation Between Ceiling Joists

  • Inner-Safe batt insulation is compression-packed and will expand to its labeled thickness.
  • Install Inner-Safe between ceiling joists, butting it strongly at all joints. The product’s fiber design allows a secure friction fit.
  • Occasionally, Inner-Safe may need cutting to fit around obstacles, such as wiring, plumbing and bracing.
  • Do not block vents.


Inspection The Installation

  • Mark and install validation tag from packaging to ease inspection.

Download Inner-Safe Install Instructions

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