What’s the Best Insulation Material for Your Roof?

If you’re asking about the best insulation for your roof, you’re already ahead of the game. Most heat loss in homes happens up top—through the attic, the rafters, and the roof deck. The right insulation up there makes a big difference in comfort, efficiency, and long-term costs. But as with most things in homebuilding, there’s no one-size-fits-all answer. It depends on your goals, your budget, and your home’s construction.
Let’s break down a few of the top contenders:
Fiberglass Batts
Best for: Budget-friendly attic floor insulation
Fiberglass is a classic for a reason. It’s affordable, widely available, and easy to install between attic floor joists. If you’re insulating an unfinished attic (meaning no HVAC or living space up there), fiberglass batts laid on the floor can be a great option. Just watch for gaps and compression—proper installation matters.
Blown-In Cellulose
Best for: Dense coverage with recycled content
Made from recycled paper and treated for fire resistance, blown-in cellulose is great for getting into every nook and cranny of your attic floor. It offers excellent coverage and performance, especially in irregularly shaped spaces. It also has solid R-value per inch and tends to be more airtight than fiberglass.
Spray Foam
Best for: Insulating the roof deck and creating a conditioned attic
If you have ductwork, HVAC equipment, or a finished attic up top, spray foam is hard to beat. It’s applied directly to the underside of the roof sheathing, creating a thermal and air barrier in one step. Closed-cell spray foam also adds some structural strength and moisture resistance. It’s the priciest option, but it can dramatically improve efficiency in the right home.
Rigid Foam Board
Best for: Tight spaces and high R-values
Rigid foam boards (like polyiso or XPS) offer high R-value per inch and are often used in cathedral ceilings or under roofing materials. They require careful sealing at the seams to prevent air leaks but can be a great solution where space is limited or where continuous insulation is needed.
So Which One Is Right for You?
Here’s a quick cheat sheet:
- You’ve got an unfinished attic and a tight budget: Go with fiberglass batts or blown-in cellulose.
- You want high performance and have HVAC equipment in the attic: Closed-cell spray foam is your best bet.
- You have a cathedral ceiling or limited space: Consider rigid foam board for its high R-value in a thin profile.
- You want eco-friendly materials: Blown-in cellulose wins for recycled content and low environmental impact.
Final Thought
Roof insulation isn’t a glamor topic, but it pays dividends every month on your energy bill. Picking the right material isn’t about what’s most expensive—it’s about what fits your house and how you live in it.
👉 Not sure what’s right for your roof? Contact us, and we’ll walk you through the options.
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How Much R-Value Do I Need? Try Our R-Value Calculator
Find out exactly how much insulation your home needs—without the guesswork. Let’s get one thing straight: when it comes to keeping your home warm in the winter and cool in the summer, R-value matters. A lot. But most homeowners (and even a few contractors) don’t really know what R-value they need, where, or why.
Find out exactly how much insulation your home needs—without the guesswork.
Let’s get one thing straight: when it comes to keeping your home warm in the winter and cool in the summer, R-value matters. A lot. But most homeowners (and even a few contractors) don’t really know what R-value they need, where, or why.
That’s why we built a free, easy-to-use R-Value Calculator—to give you clear, code-backed recommendations based on where you live and what part of your home you’re insulating.
But before you jump in and start punching in numbers, let’s cover the basics so you actually know what you’re looking at. Here's what we'll cover in this article:
- What is R-value
- Why does R-value matter
- Climate zones
- R-value calculator
What Is R-Value, Anyway?
R-value is how we measure insulation’s resistance to heat flow. Think of it like SPF for your house—higher R-value = more protection. The better the R-value, the slower your heated (or cooled) air escapes through your walls, ceilings, and floors.
So when someone says “You’ve got R-13 in your walls,” they’re talking about how well that insulation holds the line between inside and outside temperatures.
Different insulation types have different R-values per inch:
- Fiberglass batts: ~R-3.2 per inch
- Cellulose: ~R-3.5–3.8 per inch
- Spray foam (closed-cell): ~R-6.5 per inch
Why Does R-Value Matter?
Simple: it’s the difference between a home that stays comfy for cheap... and one that bleeds money every time the heat kicks on. Insufficient R-value leads to:
- Drafty rooms
- Sky-high utility bills
- HVAC systems working overtime
- Unhappy homeowners (maybe you?)
The Department of Energy and local building codes require specific R-values depending on where you live. But unless you’ve memorized the DOE’s climate zone map (we have, but we’re weird like that), figuring it out on your own is a pain.
A Quick Note on Climate Zones
The U.S. is divided into climate zones (Connecticut is mostly Zone 5), and those zones determine how much insulation your home needs.

For example:
- Zone 3 (warmer southern states) might only need R-30 in the attic.
- Zone 5 (Connecticut) usually calls for R-49 to R-60 in the attic.
- Zone 7 (northern tier)? You’re looking at R-60+ and tight air sealing.
You also need different R-values depending on whether you're insulating an attic, basement, wall, or crawlspace. That's where things get tricky.
Enter: the R-value calculator.
R-Value Calculator
We built this tool to take the confusion out of calculating R-value. Just plug in:
- Your state and county
- The part of your home you want to insulate
...and boom—you’ll get the recommended minimum and maximum R-values based on your local code and climate.
✅ No digging through PDFs
✅ No guessing
✅ No wrong answers
Whether you’re upgrading attic insulation, finishing a basement, or insulating a new addition, this calculator gives you a clear starting point. From there, we can help you figure out the right material and get the job done.
R-Value Calculator
Use the R-value calculator to find out what your home really needs—and let’s make sure you’re not under-insulated, overpaying, or leaving comfort on the table.
👉 Ready to increase your homes R value? Contact Nealon Insulation to get the job done right.

Simple Ways to Shrink Your Home's Carbon Footprint
Let’s get real. You don’t have to go off-grid, install a windmill, or start making your own soap to do right by the planet. There are everyday ways to cut down your home's carbon footprint without turning your life upside down.
Let’s get real. You don’t have to go off-grid, install a windmill, or start making your own soap to do right by the planet. There are everyday ways to cut down your home's carbon footprint without turning your life upside down.
Here are a few practical ideas to get started:
1. Ditch the Incandescents
If your home still has lightbulbs that heat up like stovetops, it’s time to upgrade. LED bulbs use up to 80% less energy and last a lot longer. They’re like the efficient little overachievers of the lighting world.
2. Be Smart (Thermostat-Wise)
Smart thermostats aren’t just a gimmick—they actually help. You can program them to run the heat or A/C only when you need it, saving you money and emissions in the process. Some even learn your habits and adjust automatically.
3. Wash Cold, Line Dry
Washing clothes in cold water gets the job done just fine 90% of the time. Combine that with skipping the dryer and using a clothesline (yes, they still exist) and you just cut down a big chunk of your home's energy use.
4. Use Power Strips (And Turn ‘Em Off)
Your TV, cable box, computer—they all sip electricity even when turned "off." Use smart power strips or just flip them off at the end of the day to stop the phantom drain. No seance required.
5. Choose Efficient Appliances
Replacing that 90s-era fridge? Look for Energy Star-rated appliances. They’re engineered to use less juice and still do the job right. Bonus: many come with rebates.
6. Cut Down on Meat (Sometimes)
No need to go full tofu, but swapping in one or two meatless meals a week can lower your household emissions. Beans and pasta never broke the bank.
7. Fix Drafts and Air Leaks
Those little gaps around windows, doors, and attic hatches are like leaky faucets for energy. Seal ‘em up and your HVAC system won’t have to work overtime.
8. Insulate the Right Way
Now let’s talk insulation—because this is the stuff people don’t think about until they’re freezing or sweating in their own homes.
Good insulation helps your home hold its temperature longer, which means less energy needed for heating and cooling. Less energy means fewer emissions. That cellulose we pack into walls, attics, and crawlspaces? It’s often made from recycled material and has a smaller footprint than most building products.
So yes—while we might be a little biased here at Nealon Insulation, tightening up your home is one of the smartest, most impactful ways to reduce your footprint long-term.
Final Thought
You don’t need to be perfect to make progress. Just a few changes around the house can make a real difference—for your utility bills and for the planet.
👉 Want help making your home more energy efficient? Contact us and let’s talk insulation that works as hard as you do.

How Much Is 1,000 Sq Ft of Insulation?
Let’s get straight to the point: insulating 1,000 square feet of space in your home can cost anywhere from $1,500 to over $5,000 depending on the material you choose and the quirks of your house. It’s like asking how much a car costs—you’ll get a different answer depending on whether you want the base model or the decked-out version with heated seats and a moonroof.
Let’s get straight to the point: insulating 1,000 square feet of space in your home can cost anywhere from $1,500 to over $5,000 depending on the material you choose and the quirks of your house. It’s like asking how much a car costs—you’ll get a different answer depending on whether you want the base model or the decked-out version with heated seats and a moonroof.
We’ll break it down by type—fiberglass, cellulose, and spray foam—and explain what drives the price up (or down).
🧱 Fiberglass Insulation: The Basic, Budget-Friendly Option
Cost for 1,000 sq ft:
👉 Around $2,000 to $3,000
Fiberglass is like the plain bagel of insulation: dependable, affordable, and everywhere. It’s often used in new construction and attics where you have open access to joists. If you're not battling extreme drafts or moisture issues, this can be a solid, cost-effective choice.
What affects fiberglass pricing:
- Open vs closed access (attic = easy, walls = more labor)
- Batts vs blown-in
- Labor needs—is it a clean install or a crawlspace contortionist job?
🌾 Cellulose Insulation: The Comfort Workhorse
Cost for 1,000 sq ft:
👉 Around $2,000 to $4,000
Cellulose insulation is what we specialize in here at Nealon. It's dense, fire-resistant, pest-resistant, and made from recycled materials. It performs great in older homes, especially for filling wall cavities without tearing your house apart.
Why the price varies:
- Dense-packing walls vs attic blow-in (walls take more time and skill)
- Access issues—we may need to drill, patch, or work around tough angles
- Depth of insulation—more R-value means more material
🧊 Spray Foam Insulation: The High-Performance MVP
Cost for 1,000 sq ft:
👉 Around $3,000 to $5,000+
Spray foam is the insulation equivalent of a triple-espresso: powerful, airtight, and overachieving. It both insulates and air seals in one shot. But it’s more expensive upfront, and not always necessary in every application.
What bumps up the price:
- Open-cell vs closed-cell (closed-cell is more expensive and higher R-value)
- Ventilation concerns—you may need mechanical ventilation if you're sealing super tight
- Prep and protection—spray foam needs careful installation to avoid overspray or damage
📈 What Else Affects the Price of Insulation?
Regardless of material, there are a few wildcard factors that can change your final number:
- Access and layout: Vaulted ceilings, narrow crawlspaces, or complicated rooflines = more labor.
- Demo or removal: If we need to rip out old insulation, that adds to the bill.
- Code requirements: Want to hit energy code or qualify for rebates? You may need higher R-values.
- Local rebates: In Connecticut, EnergizeCT rebates can significantly lower your out-of-pocket cost—especially for cellulose and spray foam.
💡 So What Should You Expect to Pay?
If you're in Connecticut and looking to insulate 1,000 sq ft, the sweet spot for most homes falls between $2,000 and $4,000. Think of that as the range for long-term comfort and energy savings.
Want a real number for your actual house? We’ll come check it out and give you a quote with no pressure and no fluff. Just real answers from real insulation nerds.
👉 Let’s talk insulation. Contact the Connecitcut insulation team.
Let's Work Together
Ready to transform your home into an energy-efficient haven? Schedule your free energy assessment today and experience the Nealon difference for yourself.