4.1301.5 Cantilevered Floor—Batt Installation

Topic:

Floors

Subtopic:

Accessible Floors

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

Single-Family Homes

Title	Specification(s)	Objective(s)
4.1301.5a 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	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 will be installed between joists and sealed 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 will be placed to the most interior edge of the top plate of the wall below	Separate cantilevered floor from conditioned floor space Allow for insulation
4.1301.5b Installation	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 will be insulated between joist from top plate of the wall below to subfloor above Cantilevered subfloor will be insulated in complete contact with the floor without gaps, voids, compressions, misalignments, or wind intrusions If kraft-faced batts are used, they will be installed with kraft facing to the 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 Insulation will be installed to prescribed R-value	Insulate to prescribed R-value
4.1301.5c Attachment	Batts will be secured with physical fasteners	Ensure insulation remains in contact with subfloor and 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
4.1301.5d Exterior soffit	Exterior soffit material will be installed and sealed	Cover and protect insulation
4.1301.5e Occupant education	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