4.1003.10 Installing Fiberglass Blown Insulation for Flat, Bowed, or Vaulted Ceilings (via Interior Access Through the Ceiling)

Attic Ceilings
For supporting material, see Building America Solution Center.
Desired Outcome: 
Consistent, uniform thermal boundary Thermal boundary The separation between the interior and exterior environments of a building that slows heat flow 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 between the conditioned space and unconditioned space
Attic, ceiling, and roof verification

All combustion appliance flues will be terminated to the exterior of the house and terminations will maintain proper clearance above snow loads

A distance no less than 2" will be maintained between any combustion appliance flue and combustible materials, unless zero clearance flue is in place

All ventilation systems will maintain a continuous connection and terminate to the outdoors

All broken mushroom vents will be replaced or removed and sealed

All plumbing stacks will be terminated to the outdoors

Non- IC IC Insulation contact rated light fixtures will be replaced with airtight IC IC Insulation contact -rated fixtures, if feasible and only when installed measures will compromise the fire rating of the fixture

All recessed lights will be labeled as having an air leakage rate no more than 2.0 CFM CFM Cubic feet per minute when tested in accordance with ASTM ASTM ASTM International, www.astm.org E 283 at a 75 pascals pressure differential

All obvious ceiling penetrations will be sealed

The space between combustion appliance flues and the ceiling will be sealed with fire-rated materials

All roof, attic, and ceiling assemblies will be structurally sound:

  • Loose ceiling panels will be secured
  • Temporary ceiling bracing will be recommended while installing installation

Dishing and pooling issues that allow standing water will be addressed

All known roof water leaks will be repaired before installing installation

Ensure occupant and worker safety

Verify attic space is ready to insulate

Ensure structural integrity of the roof and ceiling assembly

Prevent intrusion of bulk moisture

Prevent damage while installing insulation

Construction prep

Special precautions will be taken to limit fiberglass and construction dust exposure to the occupant and occupant belongings

Protect occupant health and safety

Protect occupant belongings

Attic access

Equidistant holes will be drilled in a straight row parallel to the longitudinal exterior wall of the ceiling

If a longitudinal ceiling trim piece exists, trim piece will be removed and holes will be drilled behind the trim

Hole location and size will be placed to provide access to allow for consistent and uniform coverage of installed insulation throughout the attic assembly

There will be, at a minimum, one hole between each roof truss

Holes will be large enough to accommodate the chosen fill tube without damaging the ceiling material during installation

If a vapor barrier Vapor barrier A material that retards the passage of water vapor and contains a perm rating of less than 1 or ceiling-mounted insulation is present, access will be gained through them

Attic will be visually inspected for the location of existing insulation, obstructions, hazards, and construction type

Create access to the full attic cavity

Determine insulation installation technique

Prevent damage to ceiling

Create a professionally finished ceiling

Blowing machine set up

Blowing machine pressure test will be performed with air on full, feed off, and gate closed

Hose outlet pressure will be set in accordance with manufacturer specifications

Ensure machine is capable of delivering uniform insulation density and coverage

Fiberglass blown insulation installation

Insulation will be installed to a density of 1.5 to 1.6 pounds per cubic foot

Using fill tube, 100% of each cavity will be filled to a consistent density

Fill tube will be inserted within 6" of the end of each attic cavity

Insulation will be installed into the void of the attic cavity:

  • If existing insulation is roof-mounted, insulation will be blown below
  • If existing insulation is ceiling-mounted, insulation will be blown above
  • If existing insulation is mounted at both locations, insulation will be blown in between

Flame spread and smoke-developed index for insulation will be a flame spread rating of 25 or less and a smoke development rating of 450 or less when tested in accordance with ASTM ASTM ASTM International, www.astm.org E84

Fill entire attic cavity to the prescribed R-value to reduce air infiltration Infiltration The uncontrolled passage of outside air into a building through unintended leaks in the building envelope

Avoid clogging of the cavity and the fill tube

Prevent damage to the ceiling

Fire safety will be maintained

Patching and sealing holes

Holes will be plugged or covered and sealed to be aesthetically pleasing

If existing trim was removed, it will be reinstalled

Create an airtight seal

Create a visually acceptable ceiling finish

Verification of details

Installation process will be considered complete when installer has verified that damage has not occurred to the roof or ceiling assemblies during the installation process

Verify the integrity of the house has been maintained

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