Polycro vs Tyvek vs Silnylon: Choosing the Right Groundsheet for Ultralight Backpacking

A groundsheet doesn’t look like much, but it quietly does a lot of work. It takes the abuse your tent floor would normally suffer, blocks ground moisture, and helps your sleep system stay cleaner and warmer over the long run.

Among ultralight hikers, three materials show up again and again: Polycro, Tyvek, and Silnylon. Each one has a different personality. This guide looks at how they compare and where each one makes sense—especially if you’re trying to keep your kit light.

Quick Comparison

Polycro: Ultralight and Purpose-Built

Polycro started life as window insulation film and ended up under a lot of ultralight shelters. It’s crisp, extremely light, and surprisingly tough for the thickness, as long as you’re mindful of where you pitch.

Where Polycro shines

• Among the lightest groundsheet materials available
• Packs down to almost nothing
• Excellent waterproof barrier
• Easy to replace when needed

Limitations

• Not ideal on sharp, rocky terrain
• Shorter lifespan than heavier fabrics
• Crisp feel that some hikers notice at first

If your priority is cutting weight without giving up protection, Polycro makes sense. HODRGEAR builds around that idea with:

• Ultralight Polycro Groundsheet — a simple, trail-ready barrier for your shelter floor.
• Ultralight Polycro Pack Liner (14g) — the same principle, moved inside your pack to keep your sleep system dry.

Tyvek: Built to Take a Beating

Tyvek is what you use when you expect your groundsheet to see hard use: abrasive surfaces, frequent camps in the same spot, or rough sites where weight isn’t the only concern.

Strengths

• Very high tear and abrasion resistance
• Good water resistance
• Works well on rough or dirty ground

Trade-offs

• Heavier than Polycro
• Bulkier to pack
• Noticeably loud when new

For thru-hikers counting grams, Tyvek is usually more than they want to carry. For basecamps, car camping, or harsh ground where you want something that can take abuse, it still earns its place.

Silnylon: The Middle Ground

Silnylon has been a shelter workhorse for years. It’s coated, reasonably tough, and lighter than many traditional tent fabrics. As a groundsheet material, it occupies the space between “as light as possible” and “use it anywhere.”

Strengths

• Good waterproof coating
• Quieter and softer than Polycro or Tyvek
• More durable than Polycro in mixed terrain

Trade-offs

• Heavier and bulkier than Polycro
• Can be slippery on hard surfaces
• Still vulnerable to sharp edges and punctures

Silnylon works well for hikers who want a single, all-purpose solution and aren’t chasing the lightest possible base weight.

Matching Material to Hiking Style

Polycro is a good fit if:

• You’re building an ultralight or thru-hiking kit
• You care about pack volume as much as pack weight
• You’re comfortable choosing cleaner, more careful campsites

Tyvek makes sense if:

• You expect a lot of rough surfaces
• You’re okay with extra weight in exchange for durability
• You camp in the same spot for multiple nights

Silnylon works well if:

• You want a balanced, all-round solution
• You do a mix of trips and don’t always go ultralight
• You prefer something quieter and softer under your shelter

Final Thoughts

If your goal is a focused ultralight setup, Polycro is hard to beat. It offers strong protection at a fraction of the weight and bulk of most alternatives. Combined with a liner inside your pack, it gives your sleep system a solid defense against moisture from above and below.

HODRGEAR’s Polycro options are built around that idea:

• Ultralight Polycro Groundsheet
• Ultralight Polycro Pack Liner (14g)

From there, you can add or adjust other pieces of your shelter system to match the terrain you hike and the way you like to camp.