Smart insulation starts with smart choices. While low-cost materials may look appealing, they often don’t stand the test of time—and could cost you more in repairs or replacements. Plus, not every product offers safety or snug fit. That’s where expanded cork granules stand out. This all-natural solution is resilient, moisture-resistant, and built to last.
Strong Yet Lightweight
100% Natural
Outstanding Thermal Properties
Durable Performance
Eco-Friendly Material
Safe & Easy to Use
Got questions? Here’s what you need to know.
WHAT IS EXPANDED CORK GRANULATE?
Expanded cork granules are tiny, lightweight pieces of cork that offer superior insulation compared to regular cork. They’re made by applying high heat to cork oak bark, causing it to expand and darken. No chemicals or synthetic agents—just pure thermal expansion. The magic lies in suberin, a natural resin that binds the granules together when heated.
HOW IS EXPANDED CORK USED?
Expanded cork is a popular choice in construction, and is commonly used for:
- Insulating attics, floors, ceilings, and walls—especially in tight or irregular spaces,
- Filling wall cavities and gaps in insulation systems,
- Roof insulation—poured between rafters in pitched roofs,
- Under-floor fill or structural voids,
- Leveling uneven floor or ceiling areas,
- Dry fill insulation methods,
- Creating lightweight subfloor layers.
Beyond buildings, cork is also used in:
- Terrariums—for safe, breathable bedding for reptiles and exotic pets,
- Landscaping—as mulch or decorative top layer instead of pine bark,
- Film sets—for simulating soil, rubble, or rocky terrain,
- Model making—ideal for detailed scenery or dioramas.
WHY CHOOSE EXPANDED CORK?
It’s known for its excellent insulation. Expanded cork reduces heat transfer and sound better than traditional cork. But there’s more to love:
- Lightweight—won’t stress your structure,
- Naturally mold, insect, and fungus resistant,
- Chemically inert—safe around other materials,
- Shape-holding for decades,
- Long service life,
- 100% biodegradable and eco-responsible,
- Withstands extreme temps—from –180°F to 248°F,
- Fire-safe (Euroclass E)—no toxic gas emissions during combustion.
IS IT SAFE TO HANDLE?
Absolutely. These granules are certified by the Polish National Institute of Public Health. They’re hypoallergenic, non-irritating, and safe to use. In fact, we’re the only company in Poland to hold this certification right now.
IS CORK REALLY ECO-FRIENDLY?
Without a doubt. Cork is harvested from the bark of cork oak trees—no tree felling involved. The bark regenerates every 9–12 years, and the trees themselves can live well over 200 years.
Even better, cork has a carbon-negative footprint. Cork oaks can absorb up to four times more CO₂ than most tree species.
HOW LONG DO ITS BENEFITS LAST?
Expanded cork offers long-term performance for up to 50 years or more without losing its properties.
WHAT COLOR IS IT?
It has a rich, natural dark brown color created by thermal expansion. There’s no artificial coloring added.
WHAT’S THE DENSITY?
For granules between 2–9 mm, the density averages around 70–80 kg/m³.
IS IT AVAILABLE IN SHEETS?
Yes, expanded cork sheets are also available.
HOW DOES IT COMPARE TO FOAM INSULATION?
Cork beats foam in the long run. Foam is synthetic, can degrade over time, and often has a bigger environmental toll. It can shrink, crack, or break its seal.
Meanwhile, cork offers:
- Superior durability,
- Completely safe and natural composition,
- Resilience to mold and pests,
- Biodegradability and CO₂ absorption.
HOW SHOULD I STORE IT?
Store in a dry, ventilated space. Avoid damp basements or outdoor plastic covers. Keep it away from heat sources or direct sun exposure.
Best practice: keep it dry, well-aired, and away from direct heat or moisture.
Sometimes going green gets a bad rap—as if eco-friendly means low quality. That said, no one wants to gamble with that in their home. But here’s the thing: expanded cork isn’t a risky experiment. It’s a reliable, proven solution that often outperforms many synthetic alternatives. You get both sustainability and performance—without giving one up for the other.
#1 NATURAL CORK VS SYNTHETICS – NO CONTEST
Anyone who’s tried budget synthetic insulation knows the deal: it might save you money at first, but problems often crop up soon after. Expanded cork is a different story. Install it once, and it stays effective—no refills, no patchwork, just dependable performance without relying on chemicals.
Some materials fall apart once they’re granular—they clump, disintegrate, or lose structure. That’s not the case with expanded cork. It remains fluffy, stable, and lightweight. Because real insulation isn’t about quick fixes—it’s about trusting what’s behind your walls for the long haul.
#2 ECO CHOICES ARE SMART CHOICES
Today’s world is overflowing with plastics, foams, and man-made materials that become garbage in no time—often ending up in landfills or incinerators. Their production consumes resources and pumps out CO₂ emissions. The result? Short-term products that cause lasting damage. Expanded cork isn’t part of that problem—it supports the planet and harmonizes with nature.
Here’s a twist: cork is renewable—it regrows without felling trees—yet we default to artificial options that look cheap upfront. But those carry steep environmental costs. Cork changes that equation. It leaves a minimal environmental footprint and cork oak trees actively draw down CO₂, helping to fight climate change.
#3 POPCORN EFFECT—BUT BETTER
Much like how popcorn puffs up with heat, cork undergoes a similar expansion. It starts with the bark from cork oak trees, gently harvested to preserve the tree. The bark is then heated, which causes the cells to expand, becoming porous and darkened. The heat also activates suberin—a natural plant resin—that binds everything together.
This natural transformation gives expanded cork superior insulation properties compared to raw cork. It breathes better, retains heat longer, and dampens sound more effectively.
#4 EASY TO USE & TOTALLY SAFE
Expanded cork granules are ultra-lightweight—you can move and pour them effortlessly. They’re perfect for places where rigid insulation boards won’t fit.
And here’s a major advantage: expanded cork is entirely non-toxic. It won’t irritate your skin, it's hypoallergenic, and it doesn’t emit harmful chemicals or fumes. Clean, simple, and safe—anywhere.
| Fraction | 2-9 mm |
| Volume | 2000 l (2 m³) - 140 kg |
| Color | Dark brown |
| Material | Expanded cork |
