Questions to Ask an Insulation Contractor About Attic Insulation

Attic insulation is the highest-return insulation investment in most local homes. Heat rises, and in an under-insulated attic, it escapes directly through the ceiling into the unconditioned attic space. Adding insulation here costs less per square foot than wall or basement insulation, is less disruptive to install, and typically delivers the most significant comfort and energy bill improvement of any insulation upgrade.

But attic insulation done wrong — blocking soffit vents, covering pot lights that aren’t rated for contact insulation, failing to air-seal before adding depth — can cause moisture problems, fire hazards, and ice damming that cost far more than the insulation was worth.

“The attic is where I see the most damage from poorly done insulation work. Blocked soffits that cause the attic to go damp. Insulation piled up against pot lights that aren’t IC-rated. No baffles installed, no air sealing done. The insulation itself might be fine — it’s everything that wasn’t done around it that causes the problems. The correct sequence is: air seal first, install baffles, then add insulation on top.”

— Priya Sundaram, certified insulation contractor and building envelope specialist with 16 years of experience in residential insulation and energy efficiency upgrades in the local area

Questions About Current Conditions

Will you assess the existing insulation before quoting?

A proper attic insulation quote requires the contractor to enter the attic and assess:

• Existing insulation type and depth: What’s there now, and what R-value does it represent?
• Air sealing condition: Are there obvious air bypasses — gaps around penetrations, unsealed top plates, open chases?
• Soffit ventilation status: Are baffles currently installed? Are any soffits already blocked?
• Pot light types: Are there recessed pot lights in the ceiling below, and if so, are they IC-rated (insulation contact rated) or ICAT-rated (insulation contact and airtight rated)?
• Attic hatch condition: Is it insulated and air-sealed?
• Structural access: Can all areas of the attic be reached, or are there inaccessible sections?

A quote provided without attic access is a guess.

What a good answer looks like: The contractor enters the attic, assesses current conditions, and explains what they found before proposing a scope of work.

What is the existing R-value, and what will the finished R-value be?

Ask specifically what the existing insulation level is (measured by the contractor in the attic, not estimated from the age of the home) and what the finished R-value will be after the upgrade.

Your region recommendations:
– Attic insulation: R-50 to R-60 (Natural Resources your country Climate Zone 6, which covers most regions)
– Older homes often have R-12 to R-20 — a significant gap from current recommendations

The difference between existing and target R-value determines the required depth of additional insulation.

Questions About the Installation Process

What air sealing will be done before insulation is added?

This is the most important question in attic insulation. Air sealing should precede the installation of any additional insulation — because once insulation is in place, accessing the penetrations and gaps is significantly more difficult.

Ask specifically what air sealing is included:

Top plate air sealing: The gap between the top of interior wall framing and the attic floor is a major air bypass. It should be sealed before insulation is added.

Penetration sealing: Every pipe, wire, and duct that passes from the conditioned house into the attic is a potential air bypass. Ask whether these will be sealed with expanding foam or caulk.

Pot light boxes: Recessed lights that aren’t ICAT-rated should either have airtight covers installed over them from the attic side before insulation is added, or be replaced with ICAT-rated fixtures. Non-IC-rated pot lights cannot have insulation in contact with them (fire hazard). Ask specifically how pot lights will be handled.

Attic hatch: The hatch should be weather-stripped and fitted with an insulated cover before additional insulation is installed. Ask what will be done with the hatch.

Will baffles be installed to protect soffit ventilation?

Baffles (also called rafter vents, ventilation channels, or InsulationBaffles) are rigid channels installed between each pair of rafters, from the eave edge to the attic floor, to maintain a clear air channel from the soffit vent to the open attic. Without baffles, blown-in insulation migrates to the eaves and blocks the soffit vents.

Blocked soffit vents cause:
– Moisture accumulation in the attic (condensation, mold)
– Ice damming at the eaves in winter (the warm, moist air condenses and freezes at the cold eave, backing up water under shingles)
– Premature roof deterioration

Ask specifically: Will baffles be installed at every rafter bay? What material are the baffles (rigid cardboard, foam, plastic)?

What a good answer looks like: Baffles confirmed as standard at every rafter bay, specified in writing in the quote.

Questions About Insulation Materials

What insulation material are you proposing for the attic?

Blown-in fibreglass: Loose fibreglass fibers blown into the attic. R-value approximately R-2.2 to R-2.9 per inch depending on density. Less expensive. Settles slightly over time. Good for attics that are accessible for blowing equipment.

Blown-in cellulose: Recycled paper fibers blown into the attic. R-value approximately R-3.5 per inch. Denser than fibreglass — better at resisting air movement through the insulation layer. Often preferred for attics with existing insulation that has settled unevenly.

Fibreglass batt: Rolled insulation. Used for accessible areas and specific applications. Less common for open attics where blowing is more efficient.

Spray foam (for specific areas): Used for air sealing at penetrations and sometimes for the attic hatch cover or to seal specific difficult areas, but typically not the primary insulation layer in an open attic.

Ask what material is being proposed and why it’s appropriate for your specific attic configuration.

Questions About Pot Lights

How will recessed pot lights be handled?

Recessed pot lights (pot lights, recessed lights, can lights) in the ceiling below the attic are one of the most significant sources of heat loss and air leakage in homes built in the 1990s and 2000s. They are also a fire hazard if improperly covered with insulation.

IC-rated (Insulation Contact): Insulation can physically contact the fixture. But older IC-rated fixtures may still allow air leakage.

ICAT-rated (Insulation Contact and Airtight): Insulation can contact the fixture AND the fixture is sealed to prevent air movement.

Non-IC rated: Insulation cannot contact the fixture. A minimum clearance of 3 inches must be maintained — which means blown-in insulation cannot be installed directly over these lights.

The correct approach for non-IC or non-ICAT rated lights: install an airtight cover (an airtight box) over the fixture from the attic side before insulation is installed. Ask whether the contractor inspects and addresses all pot lights during attic insulation work.

Related Questions

• Questions to Ask an Insulation Contractor Before You Hire One
• Questions to Ask an Insulation Contractor About Air Sealing
• What R-Value Do I Need for My Home?
• How Much Does Insulation Cost ?

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