Coreloft
Arc'teryx's proprietary synthetic insulation using crimped multi-denier siliconized polyester fibers. Designed for high loft, excellent warmth, and compressibility in technical outerwear.
Material Score Breakdown
7-axis material rubric, not a garment verdict — see disclosure below.
How long the fabric lasts with regular use
Softness, feel against skin, wearability
Air flow and ventilation
Heat retention and insulation
Ability to pull sweat away from skin
Environmental impact of production and disposal
How easy it is to wash, dry, and maintain
Products with coreloft
We don't have any garments containing coreloft in our catalog yet. Browse the full synthetic materials or check the product catalog.
What this score doesn't measure
This is a material rating, not a verdict on any specific garment made from coreloft. The axes above are research-backed averages for the fiber itself.
- ×Construction. Yarn staple length, weave / knit structure, stitch count, finishing. Identical fiber, very different garments.
- ×Fabric weight (GSM). A 140 GSM tee and a 220 GSM tee made of the same coreloft feel and last very differently.
- ×Dye + finishing chemicals. Beyond the three we flag (PFAS, formaldehyde, antimony), dozens of textile finishes aren't modelled.
Best For
Good warmth (84) for cold weather
Good comfort (72) and care ease (68) for casual wear
Good durability (68) and comfort (72) for office wear
Good durability (68) and breathability (58) for outdoor activities
Detailed Use Case Scores
Pros
- ✓ Excellent loft and warmth-to-weight ratio
- ✓ More compressible than most synthetic insulations
- ✓ Retains warmth even when wet
- ✓ Consistent performance in variable conditions
Cons
- ✗ Proprietary to Arc'teryx — limited availability
- ✗ More expensive than generic synthetic insulation
- ✗ Not as warm per weight as high-quality down
- ✗ Fully synthetic — not biodegradable
Better alternatives
Higher-scored synthetic materials. Same category — what to consider instead.
+8 vs Coreloft · 76/100
Membrane technology that is waterproof yet breathable. A laminate applied to other fabrics rather than a fabric itself.
+7 vs Coreloft · 75/100
Ultra-high-molecular-weight polyethylene (UHMWPE) fiber — the world's strongest fiber by weight. 15x stronger than steel, used in cut-resistant gear, ultralight backpacks, and high-performance sails.
+6 vs Coreloft · 74/100
Waterproof breathable membrane fabric (Gore-Tex, eVent, or similar technology) laminated to a face fabric. The gold standard for rain and storm protection in technical outerwear.
Care Guide
Special Notes
• Machine washable synthetic insulation
• Tumble dry low to maintain loft
Additional Care Tips
- • Machine wash cold (30°C/85°F) on gentle cycle with technical detergent
- • Tumble dry on low heat to fully restore loft
- • Do not iron — heat damages synthetic fibers
- • Do not dry clean
- • Close all zippers and Velcro before washing
- • Store hanging or loosely in a breathable garment bag
Cost
$$$$$
Premium
Shrinkage
Won't shrink with normal washing
Eco Rating
High environmental impact