Stephen Seeber
Latest
By The Numbers: Fun Findings For Five Fuzzy Fabrics
Five fuzzy insulations get measured head-to-head: Polartec Alpha Direct, Primaloft Evolve, and three Teijin Octa builds. See how structure drives air permeability, MVTR, drying rate and energy, directional R-value, and durability. Results highlight Alpha’s breathability and efficiency, Evolve’s resilience, and Octa’s structured, durable use cases for high-output backcountry layering systems.
By the Numbers: The Energy Cost of Drying Your Base Layer
Drying wet base layers with body heat demands significant energy. The choice of fabric (wool vs. synthetic) may make less of a difference under some conditions; the quantity of water is key.
By the Numbers: Another Look at Fabric Drying Performance – How can an Alpha Direct Base Layer take Longer to Dry than a Wool Base Layer?
A deep dive into the factors that cause Alpha Direct to take longer to dry than wool.
Testing Páramo Analogy Waterproof Clothing: How Well Does It Work for Rain (and Wind Shells)?
An in-depth analysis of Páramo Analogy Fabric to see how it performs in wet conditions.
By the Numbers: Can New GPS Technology Save Your Life? Under the Right Conditions, it just Might
Stephen Seeber compares iPhone and Garmin Fenix GPS tracks for accuracy and reliability.
By the Numbers: How does Tent Design and Materials Influence Cold-Weather Camping Comfort?
An overview of the complex heat exchange mechanisms between the tent occupant and the outside environment - and how to test tent construction's impact on comfort.
By The Numbers Fabric Air Permeability and MVTR are Closely Related, Just Not How You Might Expect
This work explores the relationship between air permeability and MVTR in fabrics that do not include a waterproof membrane.
By The Numbers – How Much Wind Penetrates Your Air Permeable Outer Layer at Hiking and Running Speeds?
Stephen Seeber helps us answer the question, "do air-permeable garments allow a noticeable amount of ventilation while hiking or running?"
By the Numbers: The Myth of Air Permeability in Windshirts
If one of your objectives in selecting a windshirt is eliminating moisture vapor, your selection should rely more heavily on Moisture Vapor Transmission Rate (MVTR) than Air Permeability Measurements (APM / CFM).
By The Numbers: What’s the Best Base Layer Fabric? Wool vs. Alpaca vs. Polyester
In this paper, I subject base layers in various weights made from merino, merino blends, and alpaca to the suite of tests I have developed to evaluate base layer performance. I then compare the performance of these base layers with those of the polyester base layers I have recently reviewed. We also see if my preconceived notions about merino hold water. Finally, we will see how to choose the fiber for our base layers.
By The Numbers: Patagonia Capilene Thermal Weight vs. Patagonia Capilene Midweight Performance Comparison
How does Patagonia Thermal Weight Capilene stack up against Midweight Capilene?
By The Numbers: Testing the Performance of Mountain Hardwear AirMesh Garments
Is Mountain Hardwear AirMesh a breakthrough product or a prisoner of wicking base-layer physics?
Why is my base layer soaked?
Sometimes a wet base layer just can't be avoided. Soaked-based layers happen. Here is why it will happen to you.
By the Numbers: Compression Resistance of PrimaLoft Gold vs. Climashield Apex (Part 4)
PrimaLoft Gold outperforms Climashield Apex as the more resilient (durable) insulation, capable of retaining more of its original warmth and loft in response to repeated compression.
Do moisture-wicking fabrics work?
Moisture-wicking fabrics (base layers and underwear) are designed to move sweat away from the skin. In this study, we test if Polartec and other base layer fabrics meet manufacturer claims.
Synthetic Insulation Degradation Part 2: Thermal Performance vs. Compression
How bad does high-loft synthetic insulation (Climashield Apex and Primaloft Gold) degrade when subjected to repeated compression cycles? What's the impact on backpacking gear and apparel?
By the Numbers: the Search for a High-MVTR Waterproof Breathable Shell Jacket
A high MVTR waterproof-breathable shell jacket may be the holy grail that can replace both a wind shirt and a rain jacket. Do they exist, and where do we find them?
By the Numbers: Crushing It – How Bad is Thermal Degradation in Synthetic Insulation?
In part two of this investigation, we see what happens when you crush insulation beneath a stack of concrete pavers - again and again.
The Search for a Fleece Replacement – A Close Look at Active Insulation and the role of MVTR
What is MVTR's role in active insulation garments?
Air permeability vs. moisture vapor transmission rate (MVTR): which one impacts moisture transport more in wind and rain jackets?
This study compares the performance of four jackets made with fabrics that span a wide range of air permeability rates and moisture vapor transmission rates (MVTR). The study shows that significantly greater moisture removal can be achieved as a function of jacket MVTR than jacket air permeability.
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