Insulation Scope of Work Checklist: R-Values and Air Sealing (CSI 07 21 00)

Insulation used to be simple: “Stuff the pink fiberglass in the wall and leave.”

Today, Insulation is a complex “Building Envelope” trade. With strict Energy Codes (IECC) requiring high R-Values and mandatory Blower Door Testing (air leakage), a sloppy insulation job can cause you to fail your Certificate of Occupancy.

The biggest risk for a General Contractor is the “Drafty House.” If the Insulator excludes air sealing, you will be the one caulking plates at midnight before the inspection.

To ensure your thermal envelope is compliant, use this Insulation Scope of Work Checklist (aligned with CSI Division 07).

The Standard Inclusions (The “Must Haves”)

Your bid must define the material type and density for every assembly:

• Exterior Walls: Fiberglass Batt, Mineral Wool, or Spray Foam to meet specified R-Value (e.g., R-21).
• Attic/Ceiling: Blown-in Cellulose or Fiberglass to meet R-49 or R-60.
• Floors/Crawlspace: Batts installed tight to the subfloor with wire supports (tiger teeth).
• Vapor Retarder: Installation of Kraft facing or separate 6-mil poly where required by code.
• Ventilation Chutes: Installing baffles in the attic eaves to ensure airflow from the soffit vents.

The “Scope Gaps” (Where You Lose Money)

1. Air Sealing (The “Blower Door” Guarantee)

Energy codes now require the house to be airtight (e.g., 3.0 ACH50).

• The Trap: The Insulator quotes “Batts Only.” They don’t foam the wire penetrations or caulk the top plates. The house fails the air leak test.
• The Fix: Require a “Comprehensive Air Sealing Package” (fire foam at all penetrations, caulk at plates). Ideally, include a clause: “Contractor guarantees passing Blower Door results.”

2. Window and Door Jambs

The gap between the window frame and the rough opening needs insulation.

• The Trap: The Insulator says, “The window installer should have done that.” The Window installer says, “I don’t carry foam.”
• The Fix: Assign the application of “Low-Expansion Window Foam” to the Insulation contractor. They are already on site with foam guns.

3. Soundproofing (Acoustic Batts)

Interior walls (Bathrooms, Laundry, Master Bedroom) don’t need heat insulation, but clients want sound deadening.

• The Trap: The plans don’t mark “Sound Walls,” so the bidder misses them. The client walks through after drywall and asks, “Why can I hear the toilet flushing?”
• The Fix: Explicitly list which interior walls receive “Sound Attenuation Batts.”

4. Box Sills / Rim Joists

This is the perimeter of the floor system. It is the coldest part of the house.

• The Trap: Stuffing a fiberglass batt here is often insufficient to stop air leaks.
• The Fix: Specify “Spray Foam at all Rim Joists” even if the rest of the house is fiberglass. This hybrid approach solves the draft problem cheaply.

The Foam vs. Batt Fire Safety Debate

When you transition from fiberglass batts to spray foam insulation, the rules for fire safety change significantly. Many GCs are surprised by “failed” framing inspections because they didn’t account for Fire Blocking.

Spray foam is an oil-based product; if left exposed in an attic or crawlspace, it can be a fire hazard. Code often requires:

1. Intumescent Coating: A fire-retardant “paint” sprayed over the foam in non-storage attics.
2. Thermal Barriers: 1/2” drywall or equivalent over foam in any habitable space.
3. Fire-Rated Foam: Specialized foam for sealing penetrations between floors.

Your scope of work must clarify if the Insulation Sub or the Drywall Sub is responsible for these fire-rated barriers. If you assume it’s “included” but it’s not in the bid, you’ll face a expensive change order to satisfy the building inspector.

Interface Points (Coordination)

• vs. Drywall: If the insulation is “over-stuffed” or the paper flanges aren’t stapled flat (inset stapling), the drywall will bow or “pillow.” The Insulator must “Inset staple all batts to allow for flat drywall install.”
• vs. Recessed Lights: The Insulator must ensure insulation is kept clear of non-IC rated can lights (fire hazard), or packed tight around IC-rated cans (air sealing).
• vs. HVAC: The Insulator must allow access for the HVAC return air grills and not block them with poly.

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Verifying R-Values with Bid Bench

Insulation proposals can be deceiving. A “Flash and Batt” system costs double what a “Batt Only” system costs.

Bid Bench helps you audit the thermal envelope:

1. Code Check: Our AI scans the proposal for R-Values. If your local code requires R-49 in the ceiling but the bidder proposes R-38, the system flags the violation.
2. Material Identification: It categorizes bids by type (Open Cell Foam vs. Closed Cell Foam vs. Fiberglass) so you aren’t comparing different products.
3. Scope Validation: It highlights “Air Sealing” exclusions, ensuring you don’t get stuck with a leaky house.

Pass your energy audit on the first try.
[Start your 30-day free trial of Bid Bench today.]