Attic Installation

It must follow the Massachusetts State and Local Building Codes, and following additional standards.

1 Attic Air Sealing Confirmation

Before starting the installation, the Mass Save Contractor ensures that all bypasses at chimneys, soil stacks, perimeter walls, dropped ceilings, knee wall floors and wall openings, non-IC recessed light enclosures, other attic air sealing is complete by section 6.1. In case of incomplete or incorrect sealing, Mass Save Contract must notify the program before proceeding further. 

Insulation should not be in contact with the recessed light fixtures as per section 6.1.2.k.

2 Attic Preparation

It should be according to ASTM C1015-06 and MA Basic Insulation Authorization that includes:

a. Clearance dams with 3” space installed at all masonry or double-walled metal combustion venting systems, and 6” space installed at all single wall pipe combustion venting systems.

b. Clearance dams installed at attic access, bath fans, air handlers, and between blown and storage areas.

c. Permanent damming installed around all attic hatch covers in a way they don’t interfere with the opening of the hatch cover, and that when opened will prevent insulation from falling into the living area to allow safe access into the attic.

i. The dam must have ½” thickness, tightly sealed at the base and seams, or fiberglass batt laid flat on all four sides around the hatch, or other materials approved by the PA designee.

ii. Insulation surrounding the dam must equal the R-value of the rest of the attic space;

iii. Insulation should not taper to the damming or be less because of the height of the dam.

d. Install vent chutes at all soffit vents and provide wind baffles or block under chutes

e. Ensure that all exhaust equipment ducting is terminated to the outside of the structure.

f. Provide insulation thickness markers 1/300 sq. ft. for open blow area.

3 Attic Access Doors

a. Insulate and tightly weather-strip all attic access doors.

b. Fasten rigid insulation to access hatches. If infeasible, fiberglass batts may be used.

c. Provide minimum R-14 to hatches and R-10 enclosure at the pull downstairs. The rigid foam used shall be rated for exposed use in attics on ICC ES report, and meet Sections R-316.5.4 and 316.6 requirements of IRC 2009.

d. Provide latch, hook fastener, or other mechanical closure on vertical access doors to keep them tight against weather-strip when closed.

4 Attic Venting

a. Provide attic venting per code if included in the approved Scope of Work.

b. Provide access openings to inaccessible attics where feasible.

5 Flat Attic Insulation

a. Blow in attic insulation level over entire area specified at the depth required to give the required settled R-value.
b. Use the number of bags to meet listed coverage per manufacturers’ specifications.
c. Provide attic information card as per ASTM C1015-06 and 16CFR 460 requirements.
d. The installer must sign the form provided with a date and location with the following information:
i. Insulation material installed,
ii. Installed thickness,
iii. Coverage area,
iv. Installed R-value,
v. Number of bags used or pounds installed per FTC Rule 16 CFR 460

6 Sloped Ceiling Insulation

Sloped ceilings can be densely packed as per section 6.5.3 by using cellulose.

7 Open Cavity Insulation

a. Install mineral fiber batt or blanket insulation in wall and floor open cavities to R-value in work scope.

b. This installation should be as per ASTM C1320 and ensure there are no voids, gaps, or compressions.

c. Batt insulation MUST always be installed with a warm side air barrier in contact. 

d. Batt insulation installed in walls MUST always have a solid air barrier on all six sides of the cavity.

e. Batt insulation with a kraft or foil covering must be “face stapled” to the framing. 

f. Loose-fill insulation is allowed in open walls, floors open to below, when sprayed in or blown behind netting, rigid foam, drywall, or other barriers.

8 Rigid Foam Board

Where rigid foam board is installed over mineral fiber batt insulation or on another attic surface, the listed foam board is to be used for uncovered use in the attic. Otherwise, you can install a thermal barrier or prescriptive ignition barrier as per IRC 2009 R316.5.3 and MA code. The manufacturer’s installation requirements must be followed in all cases. 

9 Floor Blocking

Where present, the knee wall floor joist opening from the attic floor to the conditioned space under the knee wall should be blocked airtight with a barrier sealed in place below the interior face of the knee wall.

10 Dense Pack Floor Insulation

At floored areas that are not accessible due to air sealing using barrier materials, Mass Save Contractor will dense pack to stop airflow. Permitted materials include:

a. Cellulose insulation at 3.5 lbs/cu ft or greater density;

b. Fiberglass wool with an air resistance at 2.2 lbs/cu ft or greater density. Also include the product information cut out from the bag with the certificate, in this case, to verify that material was tested to ASTM C522. 

Methods can include lifting one floorboard to access each cavity and inserting a 2 to 2- 1/2” insulation hose into the floor for rapid production. The material used must be confirmed to match bags used per unit area to gain the desired density targets.

Flooring removed for access to install insulation is to be replaced because of the original site condition. The flooring drilled is to be repaired with a wooden plug as per the hole diameter and set flush to the top of the floor.

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