Attic Insulation

Insulation Is Your Roof’s Best Friend

Attic insulation does two things that directly protect your roof. In winter, it keeps warm, moist air from leaking into the attic, where it condenses on the cold roof deck and causes mold, rot, and ice dams. In summer, it slows heat transfer from the living space into the attic, keeping the roof deck cooler and reducing the thermal stress that shortens shingle life. Without adequate insulation, your HVAC system works harder, your energy bills climb, and your roof ages faster.

We install blown-in fiberglass, blown-in cellulose, and spray-foam insulation in attics across all climate zones. Our approach starts with air sealing the attic floor — sealing every penetration from the living space — then adding insulation to the correct depth for your region.

Why Air Sealing Comes First

Insulation slows heat transfer. It does not stop air leakage. Warm, moist air from the living space leaks through recessed lights, plumbing stacks, electrical boxes, attic hatches, and HVAC ducts into the attic. No amount of insulation stops this airflow — you need to seal the gaps first.

• Recessed lights — every can light is a hole in the attic floor; we cover them with airtight caps
• Plumbing stacks — the gap around the pipe through the attic floor is sealed with fire-rated caulk
• Electrical boxes — we foam-seal the gap around every wire that passes through the attic floor
• Attic hatch — weatherstripped and insulated to match the surrounding insulation level
• HVAC ducts — sealed with mastic where they pass through the attic floor

Air sealing typically reduces heating and cooling costs by 10 to 20 percent on its own. Combined with proper insulation, the savings are substantial.

Insulation Types Compared

Type	R-value per inch	Cost per sq ft	Pros	Cons
Blown-in fiberglass	R-2.5 – R-3.0	$0.50 – $1.00	Lightweight, easy to install, non-settling	Lower R-value per inch
Blown-in cellulose	R-3.2 – R-3.8	$0.60 – $1.20	High R-value, fills gaps, settles naturally	Heavier, may settle over time
Spray foam (open-cell)	R-3.5 – R-3.7	$1.50 – $3.00	Air seals and insulates in one step	More expensive, professional install only
Spray foam (closed-cell)	R-6.0 – R-7.0	$3.00 – $5.00	Highest R-value, moisture barrier	Most expensive, rigid
Fiberglass batts	R-3.0 – R-3.8	$0.40 – $0.80	Low cost, DIY-friendly	Gaps around obstacles, less effective

For most attic retrofit projects, blown-in cellulose or blown-in fiberglass offers the best balance of cost, coverage, and performance. Spray foam is ideal when air sealing and insulation are combined in one step.

How We Insulate an Attic

1. Air sealing — we seal every penetration from the living space into the attic before adding insulation
2. Assessment — we measure existing insulation depth, check for moisture or mold, and verify ventilation is adequate
3. Safety prep — we lay walk boards and protect lighting fixtures and electrical panels from insulation contact
4. Blown-in application — insulation is blown through a hose from the truck to the attic floor, built up to the calculated depth for your climate zone
5. Depth verification — we measure the depth at multiple points to confirm uniform coverage and correct R-value
6. Ventilation check — we verify soffit vents are not blocked by insulation; baffles are installed at every rafter bay
7. Final inspection — we confirm the insulation level, check for gaps, and ensure the attic hatch is properly sealed and insulated

Attic Insulation Costs

Component	Typical range
Blown-in fiberglass (1,000 sq ft attic)	$1,000 – $2,000
Blown-in cellulose (1,000 sq ft attic)	$1,200 – $2,500
Spray foam (open-cell, 1,000 sq ft)	$3,000 – $6,000
Air sealing (before insulation)	$1,000 – $3,000
Attic hatch insulation	$100 – $300

The Department of Energy recommends R-49 for cold climates and R-38 for moderate climates. Most older homes have R-19 or less. Bringing an older attic up to current code typically costs $2,000 to $5,000 and pays for itself in energy savings within 3 to 7 years.

Signs You Need More Attic Insulation

• Your upper floors are significantly hotter in summer or colder in winter than the lower floors
• Ice dams form at the eaves every winter
• Your heating and cooling bills are higher than neighbors with similar homes
• The attic feels hot enough to cook in during summer
• You can see the floor joists through the existing insulation (insulation should cover the joists)
• Frost forms on the underside of the roof deck in winter

Not sure if your attic has enough insulation? Call us or request a free assessment — we will measure your insulation level, check for air leaks, and recommend the right solution for your climate.

Attic Insulation and Energy Savings

The Department of Energy estimates that proper attic insulation can reduce heating and cooling costs by 15 to 30 percent. The actual savings depend on your current insulation level, climate zone, and energy costs.

Current R-value	Target R-value	Estimated annual savings
R-11 (existing older home)	R-49	20 – 30% reduction in heating/cooling costs
R-19	R-49	15 – 25% reduction
R-30	R-49	5 – 15% reduction
R-38	R-49	2 – 8% reduction

For a typical home spending $2,000 per year on heating and cooling, upgrading from R-19 to R-49 saves $300 to $500 annually. The insulation upgrade pays for itself in 3 to 7 years and continues to save money for the life of the home.

Insulation and Roof Warranty

Your roof warranty depends on proper attic ventilation and insulation. Manufacturers require adequate attic ventilation to prevent moisture buildup and premature shingle aging. If your attic has inadequate insulation, the resulting moisture problems can void your roof warranty.

• Moisture from inadequate insulation causes deck rot, which is a structural issue not covered by roofing warranties
• Poor ventilation creates excessive heat that accelerates shingle degradation
• Ice dams caused by heat loss through the attic damage shingles and flashing — this is a maintenance issue, not a manufacturer defect
• Manufacturers may deny warranty claims if they determine the failure was caused by inadequate attic conditions

Proper insulation protects both your energy budget and your roof warranty. We ensure your attic meets the insulation and ventilation requirements that your roofing manufacturer specifies.