4.1003.4 Cape Cod Side Attic Roof—Dense Pack Installation

Attic Ceilings
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
Vapor barrier Vapor barrier A material that retards the passage of water vapor and contains a perm rating of less than 1 removal

Vapor barriers will be removed from existing attic floor

Ensure the new conditioned space is coupled with the house

Netting, fabric, rigid sheathing

When using netting or fabric, staples will be placed in accordance with manufacturer specifications, whichever is more stringent

Netting or fabric will meet local fire codes

Rigid materials will close the cavity

Secure insulation


Roof cavities will be dense packed with loose fill insulation in accordance with manufacturer density specifications

Insulation will be installed to prescribed R-value

Insulate to prescribed R-value

Onsite documentation

A dated receipt signed by the installer will be provided that includes:

  • Insulation type
  • Coverage area
  • R-value
  • Installed thickness and minimum settled thickness
  • Number of bags installed in accordance with manufacturer specifications
  • Document job completion to contract specifications

    Confirm amount of insulation installed

    Ensure ability to match bags required for total area completed

    Comply with 16 CFR 460.17

    Occupant education

    Documentation of material and R-value will be provided to occupants

    Provide occupant with documentation of installation