Batt Insulation

Detail ID
4.0401.2
Topic
Conditioned Subspaces
SubTopic
Rim/Band Joist
Desired Outcome

Continuous, contiguous, and safe thermal boundary that prevents air movement @ 50 Pascals

SF Single Family Site-Built Housing
MH Manufactured Housing
MF Multifamily Housing

Specifications

  • SF
  • MF
Specification Objective

Verify that installation area is free of:

active water leaks, fuel leaks (i.e., gas, oil, propane), and pest intrusions

energized knob and tube wiring

uncovered electrical junctions

improperly terminated devices (ventilation fans, dryers, plumbing stacks, condensate lines, combustion appliance flues/chimneys, etc.)

unshielded high-temperature devices (non-IC rated recessed lights, chimneys, flues, vents, etc.) unless they are zero clearance devices

insulation escape openings

Verify that installation area is:

intact, able to support insulation weight, and air sealed

Ensure space can be safely insulated

  • SF
  • MF
Specification Objective

Select batt insulation that has a class II vapor retarder facing and that has a flame spread and smoke development index of 25/450 or less

Select encapsulation material that is a permanent air barrier, a class II vapor retarder, and has a smoke development index of 450 or less when tested in accordance with ASTM E84 or UL 723

Select materials that are fire safe and meet class II vapor retarder requirement

  • SF
  • MF
Specification Objective

Select sealants that:

are compatible with their intended surfaces

allow for differential expansion and contraction between dissimilar materials

meet the requirements of the applicable fire safety code (e.g., thermal or ignition barriers)

Select safe and effective sealants

  • SF
  • MF
Specification Objective

Remove any existing insulation or vapor barrier materials from installation area

Prevent condensation, align thermal and pressure boundary

  • SF
  • MF
Specification Objective

Install batt insulation to prescribed R-value in every joist bay in full contact with the rim/band joist air barrier and all sides of the cavity without gaps, voids, compressions, or misalignments

If batt contains a facing material install it toward the conditioned space

Continuous and contiguous thermal boundary

  • SF
  • MF
Specification Objective

Seal each cavity airtight around the perimeter of faced batts or around the perimeter of the encapsulation material

Prevent air and moisture movement in cavity

  • SF
  • MF
Specification Objective

Post a dated receipt signed by the installer that minimally includes: Installed insulation type, coverage area, installed thickness, and installed R-value

Comply with 16 CFR 460.17 and document contract compliance

View Sub-Topic:
Rim/Band Joist