When shopping for jorts, you'll encounter terms like "12 oz selvedge" or "lightweight stretch denim" that may seem like jargon. Understanding what these specifications mean helps you make informed decisions about which shorts will work best for your climate, activities, and personal preferences. This guide breaks down the technical aspects of denim fabric in practical terms.
Denim Weight Explained
Denim weight is measured in ounces per square yard (oz/yd²). This measurement tells you how heavy and substantial the fabric is. A square yard of lightweight chambray might weigh 4-5 ounces, while the same area of heavyweight selvedge could weigh 16 ounces or more.
Weight Categories
- Ultra-lightweight (4-6 oz): Chambray and very light denim. Soft, breathable, drapes more like a woven shirt fabric than traditional denim. Best for hot climates but lacks the structured feel of heavier denim.
- Lightweight (7-9 oz): Summer-weight denim. Comfortable in warm weather while still having recognisable denim texture and some structure. Popular for casual jorts.
- Midweight (10-12 oz): The standard range for most commercial denim. Balances comfort with durability. Works well in most Australian conditions.
- Heavyweight (13-15 oz): Substantial, durable fabric that requires break-in time. More common in premium raw denim. Can be warm in summer but ages beautifully.
- Super heavyweight (16+ oz): Speciality denim for enthusiasts. Very stiff initially but develops dramatic wear patterns. Not recommended for beginners or hot weather.
For Australian jorts worn primarily in summer, 8-11 oz is the sweet spot. This range offers enough structure to look like proper denim while remaining comfortable when temperatures rise.
How Weight Affects Performance
Beyond comfort, weight influences several aspects of how your jorts behave:
- Durability: Heavier denim generally lasts longer and resists wear better, though construction quality matters more than weight alone.
- Fading: Heavier denim typically develops more dramatic fade patterns because the stiffer fabric creates sharper creases.
- Drape: Lighter denim flows and moves more, while heavier denim holds its shape more rigidly.
- Breathability: Lighter weights allow more air circulation; heavier weights retain more heat.
The Twill Weave
True denim uses a twill weave—you can identify it by the diagonal lines running across the fabric surface. This weave gives denim its characteristic durability and the ability to develop unique wear patterns over time.
How Twill Works
In a twill weave, weft (horizontal) threads pass over one or more warp (vertical) threads, then under two or more, in a regular pattern that shifts one step to the side with each row. This creates the diagonal ribbing visible on the fabric surface.
The classic denim twill uses a 3x1 pattern: the weft passes over one warp thread, then under three. The warp threads are dyed indigo while the weft threads are left white, which is why the inside of jeans is lighter than the outside.
Twill Variations
- Right-hand twill: The diagonal runs from lower-left to upper-right. More common, tends to be slightly rougher in texture.
- Left-hand twill: Diagonal runs the opposite direction. Often softer to the touch. Levi's famously uses left-hand twill.
- Broken twill: The direction changes regularly, creating a herringbone-like pattern. Reduces leg twist (where jeans gradually rotate with wear).
- Twill: True denim, diagonal lines, durable
- Plain weave (chambray): No diagonal, lighter and softer
- Dobby: Small geometric patterns woven in
- Jacquard: Complex woven patterns
Chambray vs. Denim
Chambray is often confused with lightweight denim, but it's technically a different fabric:
- Weave: Chambray uses a plain weave where threads cross over and under in a simple pattern. Denim uses a twill weave.
- Appearance: Chambray lacks the diagonal lines of denim and typically has a smoother, more uniform surface.
- Weight: Chambray is almost always lightweight (typically 4-6 oz).
- Use: Chambray is common in shirts and summer-weight shorts. It looks similar to denim but feels different.
For jorts, chambray offers maximum breathability but sacrifices the durability and distinctive aging of true denim.
Selvedge Denim
Selvedge (or selvage, short for "self-edge") is a term you'll see often in premium denim marketing. It refers to denim woven on traditional shuttle looms that create a finished edge on both sides of the fabric.
What Makes It Special
Traditional shuttle looms are slower and produce narrower fabric than modern projectile looms. The advantages include:
- Self-finished edge: The selvedge edge won't fray because it's woven, not cut. This edge is often visible when jeans are cuffed.
- Tighter weave: The slower weaving process typically creates a denser, more consistent fabric.
- Character: The process naturally creates slight irregularities that give selvedge denim personality.
Is Selvedge Better?
Selvedge indicates a particular production method, not necessarily superior quality. Well-made non-selvedge denim can outperform poorly-made selvedge. However, brands using selvedge often care more about quality overall, so it serves as a useful quality indicator.
For jorts specifically, selvedge is a nice-to-have rather than essential. The finished edge won't be visible unless you cuff significantly, and the durability difference is minimal for shorts that see lighter wear than full-length jeans.
Look for a coloured thread running along the outseam (often red, but can be any colour). This is the finished selvedge edge. In non-selvedge denim, the outseam edge is simply cut and serged.
Cotton Types and Spinning
The cotton used and how it's processed also affects denim quality:
Cotton Varieties
- Upland cotton: The most common type, accounting for about 95% of world production. Perfectly adequate for good denim.
- American Supima: Premium long-staple cotton that produces softer, stronger yarn. More expensive but more durable.
- Zimbabwe cotton: Known for irregular texture that creates vintage-look denim.
- Japanese organic cotton: Prized for quality and grown without synthetic chemicals.
- Australian cotton: High quality, often grown sustainably. Worth looking for in locally-made products.
Spinning Methods
- Ring-spun: Traditional method that produces stronger, smoother yarn. The fibres are aligned and twisted together. Look for this in quality denim.
- Open-end/rotor-spun: Faster, cheaper process that produces fuzzier, slightly weaker yarn. Common in mass-market denim.
Ring-spun cotton creates denim that fades more evenly and develops better wear patterns over time. It's a reliable quality indicator when shopping.
Denim Finishes and Treatments
Most denim undergoes various treatments after weaving:
Washing
- Raw/dry: Unwashed after dyeing. Stiff initially but softens with wear. Shrinks when first washed.
- One-wash: Single wash to remove shrinkage and excess dye. Softer than raw but still fairly rigid.
- Stone-wash: Washed with pumice stones to create worn-in appearance and softer hand.
- Enzyme-wash: Uses enzymes to break down fibres for softness without the inconsistency of stone-washing.
Distressing
- Sanding: Mechanical abrasion creates worn patches.
- Laser treatment: Modern, water-efficient method to create fade patterns.
- Chemical wash: Bleach or other chemicals create colour variation.
Sanforization
Most commercial denim is "sanforized"—pre-shrunk during manufacturing to minimise shrinkage after purchase. Raw denim enthusiasts often prefer unsanforized fabric that can shrink 3-10% when first washed, resulting in a custom fit.
Practical Application
When shopping for jorts, use this knowledge strategically:
- For hot weather: Look for 8-10 oz weights, preferably ring-spun cotton
- For durability: Heavier weights (11-13 oz) and quality construction matter more than selvedge
- For unique fading: Raw or one-wash denim in heavier weights
- For immediate comfort: Pre-washed, enzyme-washed, or stretch denim
Understanding these fundamentals won't make you a denim expert overnight, but it provides the vocabulary to evaluate products, understand marketing claims, and make choices aligned with your actual needs rather than brand hype.