Specifications

2008 Residential Appendices RA3-29
Appendix RA3 – Residential Field Verification and Diagnostic Test Protocols
• The batt shall be friction fitted into the cavity unless another support method is used.
• Batt insulation shall be installed to fill the cavity and be in contact with the sheathing on the back and
the wallboard on the front - no gaps or voids.
• Batts with flanges that are inset stapled to the side of the stud must be flush with the face of the cavity
(or protrude beyond) except for the portion that is less than two inches from the edge of the stud.
• Non-standard-width cavities shall be filled with insulation fitted into the space without excessive
compression.
• Batt insulation shall be cut to butt-fit around wiring and plumbing, or be split (delaminated) so that one
layer can fit behind the wiring or plumbing, and one layer fit in front.
RA3.5.4.2 Narrow-Framed Cavities
•
Non-standard width cavities ¼ inch or wider shall be filled by batt insulation cut to snuggly fit into the
space or filled with loose fill insulation or expanding foam.
• Narrow spaces (two inches or less) at windows, between studs at the building's corners, and at the
intersections of partition walls shall be filled with batt insulation snuggly fitted into the space (without
excessive compression), loose fill insulation, or expansive or minimally expansive foam.
RA3.5.4.3 Special Situations
RA3.5.4.3.1 Installation
s Prior to Exterior Sheathing or Lath
• Hard to access wall stud cavities such as;0 corner channels, wall intersections, and behind
tub/shower enclosures shall be insulated to the proper R-value. Special care shall be taken to insure
the above cavities are air tight. This may have to be done prior to the installation of the exterior
sheathing or the stucco lath.
RA3.5.4.3.2 Obstruc
tions
• Insulation shall be cut to fit around wiring and plumbing without compression.
• Insulation shall be placed between the sheathing and the rear of electrical boxes and phone boxes.
• In cold climates, where water pipes may freeze (Climate Zones 14 and 16) pipes shall have at least
2/3 of the insulation between the water pipe and the outside. If the pipe is near the outside, as much
insulation as possible shall be placed between the pipe and the outside (without excessive
compression), and no insulation shall be placed between the pipe and the inside.
RA3.5.4.3.3 Rim
Joists
• All rim-joists shall be insulated to the same R-Value as the adjacent walls.
• The insulation shall be installed without gaps or excessive compression.
RA3.5.4.3.4 Kneewalls and Skylight
Shafts
• All kneewalls and skylight shafts shall be insulated to a minimum of R-19.
• The insulation shall be installed without gaps and with minimal compression.
• For steel-framed kneewalls and skylight shafts, external surfaces of steel studs shall be covered with
batts or rigid foam unless otherwise specified on the Certificate of Compliance using correct U-factors
from Joint Appendix JA4, Table 4.3.4 (or U-factors approved by the Commission Executive Director).
• The house side of the insulation shall be in contact with the drywall or other wall finish.
• The insulation shall be supported so that it will not fall down by either fitting to the framing, stapling in
place with minimal compression, or using other support such as netting.
RA3.5.4.3.5 HVAC/Plumbing Closet