Insulation Savings Calculator

No R-values. No technical charts. Just answer a few questions about what you see — and we'll show you what your attic is costing you.

Why your attic matters most: Heat rises. In winter, warm air is constantly pushing up and out through your ceiling. In summer, a hot attic radiates heat down into your living space. The attic floor is the single most cost-effective place to stop that — and most older homes are dramatically under-insulated there.

Tell Us About Your Home

Answer what you know. You don't need a tape measure or any technical background — just a quick look in your attic hatch.

1. Where do you live?
Pick the closest match — this affects how hard your home works to stay comfortable.
2. Take a peek into your attic hatch. What do you see?
Look at the wooden framing members (joists) that run across the attic floor. How high does the insulation come compared to them?
3. How much do you want to improve it?
More insulation delivers more benefit — but with diminishing returns. The biggest gains come from the first major upgrade.
4. What do you pay to heat and cool your home?
Average monthly amounts are fine — a rough estimate gives a useful ballpark.
Gas, oil, electric heat, or a portion of your electric bill
Air conditioning — enter 0 if you don't use AC

What's Actually In Your Attic

Current insulation
After upgrade
Less heat loss through ceiling
Estimated Annual Savings
Monthly Savings
Heating Bill Savings/Year
Cooling Bill Savings/Year

🌡️ What This Means for Your Comfort

Honest context:

Why Ceiling Insulation Has Such a Big Impact

Heat doesn't just leak through the walls — it rises. In winter, warm air naturally moves upward and escapes through the least-resistant path it can find: your ceiling. In summer, a sun-baked attic can reach 140°F or more, and that heat radiates down into your living space no matter how well your AC runs.

The ceiling separating your living space from your attic is where most homes give up the most heat. And because attic access is usually easier than walls, adding insulation up there delivers a better return than almost any other envelope improvement.

Here's how upgrading translates to real heat loss reduction through the ceiling:

Starting PointUpgrade ToHeat Loss Reduction
Bare / minimal (R-3)DOE Recommended (R-38)92%
Thin, old insulation (R-7)DOE Recommended (R-38)82%
3–4 inches (R-11)DOE Recommended (R-38)71%
5–7 inches (R-19)DOE Recommended (R-38)50%
8–10 inches (R-30)High Performance (R-49)39%
DOE Minimum (R-38)Maximum (R-60)37%

Note: The biggest gains come from the worst-insulated homes. Diminishing returns set in as R-values climb — going from R-3 to R-38 saves far more than going from R-38 to R-60.

Common Questions About Attic Insulation

How do I know if my attic insulation is adequate?

Look into your attic hatch. If you can clearly see the wooden joists (the framing boards) sticking up above the insulation, you're almost certainly under-insulated. The Department of Energy recommends that insulation cover and bury the joists entirely — typically 10 to 16 inches of blown-in material for most climates. Visible joists are the clearest sign you're losing more heat than you need to.

Does adding insulation really improve comfort, not just my energy bill?

Yes — often more noticeably than the savings. Better ceiling insulation reduces the cold radiant surface overhead in winter and the hot ceiling in summer. Your body is constantly exchanging heat with the surfaces around it, not just the air. Rooms feel more comfortable at the same thermostat setting. Many homeowners notice the comfort improvement before they see any change in their bill.

Should I add insulation before replacing my HVAC system?

In most cases, yes. Insulating first reduces your home's heating and cooling load, which means you may need a smaller, less expensive HVAC system — and any system you install will run more efficiently and last longer. Oversizing HVAC in a poorly insulated house is one of the most common and expensive mistakes in home energy upgrades.

Can I add new insulation on top of my old insulation?

Usually yes, for blown-in or batt insulation in attics. However, if your existing insulation is wet, compressed, or contaminated, address that first. Most importantly: air seal the attic floor before adding new insulation on top. Blown-in insulation laid over open gaps around light fixtures and pipe penetrations won't reach its rated performance because air can still move freely through those openings.

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