Are Insulation Boards Flammable? Understanding Fire Safety in Insulation Materials
If you’re picking insulation for your home or a job site, fire safety isn’t just a fine-print detail—it’s something you need to think about up front. I’ve been in this business since bell bottoms were still in style, and let me tell you: not all insulation boards are created equal when it comes to handling heat.
So, are insulation boards flammable? Well… some of them absolutely are. Others? Built like a fireman’s jacket. Here’s the no-fluff rundown on the main types we work with, and what you need to know to keep your space safe.
1. Polyisocyanurate (PIR): The Overachiever With a Caveat
PIR boards are stiff, high-performance foam panels—popular in walls, roofs, and anyone looking for big R-values in a slim package.
🔥 Will it burn? Eventually, yes. PIR boards are less flammable than other foam boards because they’ve got fire retardants baked in. They tend to char instead of going up like a tiki torch. But hit them with serious heat, and they’ll still catch and send off toxic smoke.
✅ What to do: Always cover PIR with a fire-rated barrier—like drywall. Never leave it exposed in finished spaces.
2. XPS: Tough Against Moisture, Not Against Flame
Extruded polystyrene (XPS) is what you’ll find behind a lot of foundation walls and under slabs. Great for water resistance, not so great for fire.
🔥 Will it burn? Like dry pine in August. Even treated XPS can ignite and gives off thick, nasty smoke when it does.
✅ What to do: XPS should never be left uncovered indoors. Wrap it up tight behind something non-combustible—gypsum board is your friend here.
3. EPS: Cheap, Light, and Quick to Catch
Expanded polystyrene (EPS) is kind of the little brother to XPS—lightweight, inexpensive, and used in packaging, walls, and roofs.
🔥 Will it burn? Oh yeah. Faster than XPS, in fact. It’s got a lower melting point and will absolutely feed a fire if you let it.
✅ What to do: If you’re going to use EPS, bury it completely behind non-combustible materials. Think of it like kindling—treat it with caution.
4. Mineral Wool (aka Rockwool): Built From Lava, Basically
Now we’re talking. Mineral wool is made from spun rock and industrial slag. It’s dense, durable, and basically fireproof.
🔥 Will it burn? Not a chance. It’s non-combustible and holds up to temps north of 1,800°F. I’ve seen it used in fire-rated assemblies, and it doesn’t even blink.
✅ What to do: If fire resistance is your top concern, this is your MVP. No special treatment needed—install and sleep easy.
5. Fiberglass: The Old Reliable (With a Caveat)
Fiberglass boards are another non-combustible option made from—you guessed it—glass fibers. Great for ductwork, ceilings, and wall cavities.
🔥 Will it burn? The glass itself won’t. But if your board has a kraft paper or foil facing? That can ignite if exposed to flame or heat.
✅ What to do: Keep faced fiberglass away from open flames, light fixtures, or anything that gets hot.
Fire Safety 101 (From a Guy Who’s Seen Some Things)
Whatever insulation you’re working with, there are a few universal rules that’ll keep you out of trouble:
✔ Cover your foam. XPS and EPS should never be exposed in a finished space. Always wrap ‘em up in drywall or cement board.
✔ Know your codes. Every town has its own rules. Follow your local building codes like your roof depends on it—because it does.
✔ Vent properly. Trapped heat can turn a safe attic into a fire trap. Good airflow helps prevent that.
✔ Install smoke detectors. Especially near new insulation work. Cheap insurance.
✔ Use fire-rated products when you can. Mineral wool and fiberglass might cost a bit more, but they’re way safer in a pinch.
So… Are Insulation Boards Flammable?
Some are. Some aren’t. If you’re using foam—like XPS or EPS—just assume it burns and plan accordingly. If you want the peace of mind that comes with fire resistance, mineral wool or fiberglass is the way to go.
And if you're not sure what makes sense for your home? That’s why we’re here. At Nealon, we’ve been insulating Connecticut homes since 1977. We know the products, we know the codes, and we know how to do the job right the first time.
📞 Give us a shout if you’ve got questions or need a quote. We’re happy to walk you through your options—no pressure, no BS. Just honest advice from folks who’ve been doing this for nearly 50 years.
Let’s make sure your insulation does its job without becoming a fire risk.
p.s Cellulose insulation isn't flammable
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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.
10 Free or Cheap Ways to Keep Your Connecticut Home Cooler This Summer
Connecticut summers don’t mess around. One day it’s a nice breeze off the Sound, the next it feels like your house turned into a baked potato. But before you crank the AC to the point where your electric bill starts sweating too, here are ten ways to beat the heat—without breaking the bank.
Connecticut summers don’t mess around. One day it’s a nice breeze off the Sound, the next it feels like your house turned into a baked potato. But before you crank the AC to the point where your electric bill starts sweating too, here are ten ways to beat the heat—without breaking the bank.
1. Shut the blinds like it’s your job
Seriously. About 30% of unwanted heat comes from your windows. Keep blinds and curtains closed during the hottest parts of the day—especially on south- and west-facing windows. Blackout curtains? Even better.
2. Box fans + window trick = poor man’s AC
Point a box fan out the window in the evening to blow hot air out while you crack a window on the cooler side of the house. It creates a little air current that pulls cool air in and shoves hot air out.
3. Switch your ceiling fans to “summer” mode
Yes, they have a summer setting. There’s usually a little switch near the base. Flip it so the fan spins counterclockwise—this pushes air down and creates a cooling breeze instead of just stirring the soup.
4. Ditch the incandescent bulbs
Old-school bulbs run hot. Swap 'em out for LEDs and your rooms stay a few degrees cooler. Plus, it cuts your electric bill. Win-win.
5. Cook less—or cook outside
Using the oven or stove heats up your kitchen like a pizza shop. Grill outside, eat more cold foods, or prep meals early in the day. Your house (and your face) will thank you.
6. Seal the air leaks
You know those little cracks around windows, doors, and basement bulkheads? They’re like VIP entry for hot air. Caulk, weatherstripping, and a little bit of foam sealant can go a long way. Not sure where the leaks are? We can help air seal your home.
7. Close off unused rooms
No need to cool the guest room your in-laws use twice a year. Shut the doors to rooms you’re not in—this keeps the cooler air circulating where you actually need it.
8. Use bathroom and kitchen exhaust fans
These fans aren’t just for smells and steam—they pull hot air and humidity right out of the house. Use 'em during and after cooking or showering to help the whole place cool down faster.
9. Add some attic insulation
Yep, insulation isn’t just a winter thing. A poorly insulated attic turns into a giant heat battery that radiates down into your living space all day long. Dense-packed cellulose can help keep that heat out in the summer and in during the winter.
10. Schedule an energy audit
If your home feels like a sauna every summer, there’s a reason. A free or low-cost energy audit (like the ones offered through EnergizeCT) can pinpoint the exact spots your house is losing the fight against heat—and help you qualify for rebates to fix them.
Why Insulation Helps You Run the A/C Less
Think of insulation like a cooler—just like it keeps the cold in and the heat out, your home can do the same when it’s properly insulated.
Without insulation (or with old, crusty, half-bald insulation), all that nice cold air your A/C is working so hard to produce? It slips right out through your attic, walls, and basement like water through a colander. And the hot summer air outside? That stuff seeps in like an uninvited guest.
Add proper insulation—especially in your attic and walls—and suddenly, your A/C doesn’t have to work nearly as hard. You cool the house down once… and it stays cool. That means:
- Lower energy bills
- Less wear and tear on your HVAC system
- More consistent comfort (no more sweatbox upstairs and meat locker downstairs)
Bottom line: good insulation gives your air conditioning a break—and your wallet one, too.
👉 Want to make your home cooler, quieter, and cheaper to run this summer? Let’s make a plan.
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.