4.1103.1 Dense Pack Exterior Walls

Topic: 
Walls
Subtopic: 
Enclosed Walls
Desired Outcome: 
Consistent, uniform thermal boundary Thermal boundary The separation between the interior and exterior environments of a building that slows heat flow between conditioned and unconditioned space to prescribed R-value of an adjoining insulated assembly
For supporting material, see Referenced Standards and Building America Solution Center.
TitleSpecification(s)Objective(s)
4.1103.1a
Exterior dense pack Dense pack The process of installing loose-fill insulation to reduce air flow and perform to a stated R-value

Using fill tube or an alternative method as approved by the authority having jurisdiction, 100% of each cavity will be filled to a consistent density:

  • Cellulose insulation used in an enclosed cavity will be installed at 3.5 pounds per cubic foot or greater density
  • Blown fiberglass, mineral fiber, or rock and slag wool used in an enclosed cavity will be installed at or above the manufacturer recommended density to limit air flow that corresponds to an air permeance value of 3.5 cfm CFM Cubic feet per minute /sq. ft. at 50 pascals, as measured using ASTM ASTM ASTM International, www.astm.org C 522, E 283, or E 2178; the number of bags installed will be confirmed and will match the number required on the coverage chart
  • All holes and penetrations will be plugged and/or sealed

Insulation will be verified to prevent visible air movement using chemical smoke at 50 pascals of pressure difference

Eliminate voids and settling

Minimize framing cavity air flows

4.1103.1b
Onsite documentation
A dated receipt signed by the installer will be provided that includes:
  • Coverage area
  • Thickness
  • R-value

Document job completion to contract specifications

Confirm amount of insulation installed Comply with 16 CFR 460.17