MH - Blown Insulation for Flat, Bowed, or Vaulted Ceilings (via Interior Access Through the Ceiling)

Detail ID 4.0103.12
Attic Floors - Unconditioned Attics
Desired Outcome

Continuous, contiguous, safe, and compliant thermal barrier installation that protects integrity of interior surfaces and client health

SF Single Family Site-Built Housing
MH Manufactured Housing
MF Multifamily Housing


  • MH
Specification Objective

Verify that installation area is free of:

active water leaks, fuel leaks (i.e., gas, oil, propane), and pest intrusions

uncovered electrical junctions

improperly terminated devices (ventilation fans, dryers, plumbing stacks, condensate lines, combustion appliance flues/chimneys, etc.)

unshielded high-temperature devices (non-IC rated recessed lights, chimneys, flues, vents, etc.) unless they are zero clearance devices

insulation escape openings

Verify that installation area:

is intact, able to support insulation weight, and air sealed

Ensure space can be safely insulated

  • MH
Specification Objective

Select loose fill fiberglass insulation that has a flame spread and smoke development index of 25/450 or less when tested in accordance with ASTM E84 or UL 723

Select fire safe insulation

  • MH
Specification Objective

Select sealants that:

are compatible with their intended surfaces

allow for differential expansion and contraction between dissimilar materials

meet the requirements of the applicable fire safety code (e.g., thermal or ignition barriers)

are low volatile organic compound (VOC) sealants for use inside the pressure boundary that meet independent testing and verification protocols

Select safe, durable, and effective sealants

  • MH
Specification Objective

Setup a dust control enclosure for all interior access locations that limits insulation and construction dust exposure to the occupant and occupant belongings

Prevent occupant exposure to construction dust

  • MH
Specification Objective

Drill equidistant holes in a straight row parallel to the longitudinal exterior wall of the ceiling

If a longitudinal ceiling trim piece exists, remove trim piece and drill behind the trim

Choose access hole locations that allow for consistent and uniform coverage of installed insulation; at a minimum there will be one hole between each roof truss

Drill holes that are large enough to accommodate the chosen fill tube without damaging the ceiling material during installation

If a vapor barrier or ceiling-mounted insulation is present, gain access through them

Create safe access to entire cavity

  • MH
Specification Objective

Fill entire attic to prescribed R-value

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

Continuous thermal barrier of consistent R-value

  • MH
Specification Objective

Install closure system over all access holes that is airtight, durable, and aesthetically pleasing

If existing trim was removed, reinstall it as originally installed

Airtight, durable, and aesthetic access closure

  • MH
Specification Objective

Post a dated receipt signed by the installer that minimally includes: Installed insulation type, coverage area, installed thickness, minimum settled thickness, installed R-value, and number of bags installed

Comply with 16 CFR 460.17 and document contract compliance