What Is Microgrid Fleece? The Fabric Behind Packable Warmth

Ask someone to picture "warm" and they usually picture bulky, a jacket that eats half a suitcase and leaves you sweating the second you stop moving. Microgrid fleece breaks that assumption, and it's worth understanding before it shows up in more of what outdoor brands, ours included, put on shelves.

The short answer: microgrid fleece is a waffle-pattern fabric construction, a grid of small raised squares, that maximizes warmth while minimizing weight and bulk. The raised texture increases surface area, which is exactly what makes it both more breathable and faster-wicking than a flat, solid fleece.

What "microgrid" actually describes

It's a construction method, not a brand. The grid pattern creates small air pockets that trap warmth while channels between the raised squares let sweat move and evaporate faster than it would through a smooth, solid fleece.

Why it packs smaller than a regular sweater

The tradeoff that makes microgrid fleece useful: less bulk per unit of warmth. It lands between a base layer and a mid-layer, light enough for three-season use and for staying warm while actually moving, rather than just sitting still.

Where it shines, and where it doesn't

Microgrid fleece performs best as a mid-layer, worn under a wind-resistant shell, since the open grid structure that makes it breathable also means limited wind resistance on its own. For a packable warm layer that disappears into a bag until it's needed, that tradeoff is usually worth it.

Why we're building ours around this construction

Our upcoming fleece uses a 200 GSM Polartec Power Grid fabric specifically for this reason, a recognized, tested version of the same grid construction, chosen for warmth without the bulk.

Quick FAQ

• Is microgrid fleece warmer than regular fleece?
  Generally no, ounce for ounce it trades some raw warmth for breathability and lower bulk, which matters most when you're moving rather than standing still.
• Can it be worn alone, or does it need a layer over it?
  It works alone in mild conditions, but pairing it with a wind-resistant outer layer is where it performs best in real cold.
• Does it work the same for kids and adults?
  Yes, the fabric properties don't change, though fit and layering needs will differ by activity level and age.
• How does it compare to the ONE Shirt for warmth?
  The ONE Shirt is a base layer, built for next-to-skin wear in any season. Microgrid fleece is a mid-layer, worn over a base layer specifically for added warmth, the two are built to work together, not replace each other.