4.1103.4 Dense Packing Blown Insulation

Enclosed Walls
Desired Outcome: 
Maintain a consistent, uniform thermal and weather-resistant boundary between conditioned and unconditioned space to prescribed R-value of an adjoining insulated assembly
For supporting material, see Referenced Standards.
Worker safety

All worker safety specifications will be in accordance with SWS 2.0100 Worker Safety

Lead safety procedures in buildings built before 1978 will be followed, unless approved testing method proves absence of lead based paint in surfaces that will be disturbed 

Ensure worker safety, especially in regard to fall protection considerations and contaminants found in demolition, such as asbestos, lead, polychlorinated biphenyls, etc.

Occupant safety

Occupant will be notified of changes or repairs to be made

An occupant safety plan will be prepared and implemented

Ensure occupant safety


Conduct pre-inspection in accordance with SWS 2.0100.4 Worker Safety

Gaps, cracks, and holes in fire separations located within the work area will be visually identified and incorporated into air sealing work scope, including those that span two conditioned or unconditioned spaces

Where drawings are available that identify specific fire-resistance ratings (i.e., 1 hour, 2 hour), materials and methods will be employed to preserve or restore such rating

Where drawings are unavailable or do not identify specific fire-resistance ratings, the fire-resistance rating of the assembly may be inferred from the current construction (i.e., single 5/8 sheetrock, concrete masonry unit), and materials and methods employed will be consistent with restoring or preserving such inferred fire-resistance rating

Repairs necessary to stabilize work areas and protect or preserve the integrity of energy improvement will be completed before work begins

Insulation will not be installed if moisture-related issues are not resolved

Existing water control measures will be identified

Air sealing locations on the exterior walls will be identified

Air sealing will be completed before installing insulation

Identify and remediate pest, moisture, air leakage, and electrical problems before insulation installation

Ensure a durable, continuous thermal boundary Thermal boundary The separation between the interior and exterior environments of a building that slows heat flow

Avoid compromising existing water control system

Wall access

When feasible, insulation will be installed into cavities from the exterior side of the wall

When feasible, exterior cladding at the insulation access point will be removed before creating an access hole through the sheathing

Insulation access point will be created to minimize air barrier Air barrier The separation between the interior and exterior environments of a building that slows air flow to the point that no smoke movement is visible at 50 pascals of pressure difference across the boundary and drainage plane disruption

Access point will be sealed to be airtight and watertight after insulation installation before reinstalling the exterior cladding

Water management system will be repaired to function as originally intended (e.g., lapping new felt paper underneath the upper and over the lower joint of the existing felt paper)

Ensure occupant health and safety

Minimize disruption within the units

Avoid compromising existing water control system

Minimize air and moisture flow through the wall system

Sealant selection

Sealants will be compatible with their intended surfaces and applied in accordance with manufacturer specifications

Selection will be durable, pest resistant, and have a weather-appropriate seal

Indoor sealants will be low volatile organic compound ( VOC VOC Volatile organic compound ) products that meet independent testing and verification protocols, such as Green Seal GS-36, "GREENGUARD Children and Schools," or comparable certifications

Fire-resistance-rated assemblies will be provided with sealants permitted by the authority having jurisdiction and adopted building code

Prevent intrusion of moisture and pests into the sealed assembly

Prevent exposing workers or occupants to excessive VOC VOC Volatile organic compound levels

Ensure sealant meets or exceeds the performance characteristics of the assembly and is compliant with local fire code requirements

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, 100% of each cavity will be completely 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, rock and slag wool, or spray foam used in an enclosed cavity will be installed in accordance at or above manufacturer recommended density to limit air flow that corresponds to an air permeance value of 3.5 cubic feet per minute/square feet at 50 pascals, as measured using the following applicable methods: ASTM ASTM ASTM International, www.astm.org C 522, or ASTM ASTM ASTM International, www.astm.org E 283, or ASTM ASTM ASTM International, www.astm.org E 2178
  • All insulation materials used will meet ASTM ASTM ASTM International, www.astm.org E84 flame spread/smoke development rating of 25/50
  • The number of bags installed will be confirmed and will match the number required on the coverage chart

Insulation will be verified to prevent visible air movement at 50 pascals of pressure difference using  chemical smoke or other approved verification method by the authority having jurisdiction

Eliminate voids and settling

Minimize framing cavity air flow

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