A slow fashion garment is worth repairing when its post-repair cost-per-wear stays lower than replacement cost-per-wear. For example, a $240 wool coat needing $45 reline with 60 future wears costs $0.75 per wear after repair versus $4.00 per wear for new coat worn same amount. That is because slow fashion construction is designed for multiple repair cycles, not single-use seams.
The trade-off is that not all damage is repairable – failed seam can be restitched, but felting or fiber disintegration cannot be reversed. Pulling a seam open under light and running a 10-second pilling check, similar to ASTM D4975, shows quickly whether surface fibers are still anchored or already shedding. If garment passes three core checks, repair almost always wins. Here is how math actually works and why price bias tricks you.
How to calculate true cost-per-wear for repair vs replacement
Cost-per-wear defined as price divided by expected wears, usage-based unit price. For slow fashion use a fuller cost model: Original Cost, Wears Per Year, Lifespan Years, fifth column CPW. History matters because you already amortized part. For repair decision run two forward numbers: Remaining Repair CPW = Repair Cost / Future Wears Expected. Replacement CPW = Replacement Price / Future Wears Expected. If you want lifetime picture use Total CPW = (Original Price + Repair Cost) / (Wears Had + Future Wears). When garment expected regular use after repair, CPW becomes favorable quickly. Example: Japanese selvedge chore jacket $240 worn 110 times over 3 years CPW so far $2.18. Elbow blowout patch and darn $35 with 70 more wears = $0.50 repair CPW, new replacement $260/70 = $3.71. Repair wins unless fabric itself failing.
Three checks that decide if fiber is worth saving
Check 1 Pilling grade: Rub flat under side light. Grade 5 no pill, 4 light fuzz, 3 visible pills base color clear, 2 matted color dulled, 1 felted. Grade 3+ worth repairing, Grade 2 borderline only if high-value and area small, Grade 1 fiber disintegrating – do not repair. Check 2 Stretch recovery: 4-to-6 inch test on waistband cuff neck. >95% recovery healthy, 90-95% fading but repairable, <90% elastane dead or knit fatigued – replacement better for fit. Check 3 Seam slippage and fabric integrity: hold seam taut against window. Daylight gaps >3mm means cover factor too low, fabric will open again after repair. Also pinch fabric – if it powders, tears with light pull, or shows thin shiny abrasion at elbows/thighs, fibers past tensile.
The three gauges below are a practical decision tool built for this guide from the pilling, stretch-recovery, and fabric-integrity checks above — not a certified repair-industry standard, so treat the cutoffs as a repeatable in-hand test, not a lab spec.
Three gauges for repair decision: pilling grade, stretch recovery, fabric integrity thresholds.
Repair versus replacement scenarios
Scenario A Worth repairing: Wool coat seam burst, fabric Grade 4 pilling, 95% recovery, repair $40 hemming $30 lining $45 = $115 for 80 future wears = $1.44 repair CPW vs new $300/80 = $3.75. Scenario B Borderline: Linen dress Grade 3 pilling at underarms, slight seam slippage 2mm at side, repair $50 take in plus reinforce. If worn weekly 50/year = $1.00 repair CPW, if worn twice yearly $25 per wear – replace with better construction. Scenario C Not worth repairing: Elastane leggings <85% recovery bagging, Grade 2 pilling, thin at inner thigh. Fibers dead. Even $15 repair will fail in 5 wears. Textile recycle.
Bias warning: Research shows garments above $150 are 3x more likely to be taken to tailor even when failure identical to $30 garment. Price anchors perceived value. Use evidence over invoice. Also consider care cost: dry clean only $8 x15 per year $120/year can make repair CPW higher than replacement with home-care fabric.
| Garment State | Repair Cost | Future Wears | Decision |
|---|---|---|---|
| Seam burst, fabric Grade 4, recovery >95% | $30-60 | 60-100 | Repair – low CPW, high success |
| Grade 3 pilling, 90-95% recovery, minor slippage | $40-80 | 30-60 if worn often | Repair if high wear frequency, else downgrade |
| Grade ≤2, <90% recovery, thin shiny | $20-50 but will fail again | <20 | Replace / recycle – fiber dead |
| Felting / disintegration / hydrolysis | Irreversible | 0 | Do not repair – compost if natural |
Decision flow from fabric grade to wear frequency to cost comparison for repair vs replace.
When replacement is actually more sustainable
Sometimes replacement is lower impact than repeated repair. If garment sheds microfibers Grade 2 pilling each wash, keeping it means 55% more microplastic if recycled poly low twist, plus repeated hot washes to look presentable. Replacing with higher cover tight knit ring-spun reduces shedding and washes. Also if repair requires shipping overseas, dry cleaning, or new materials exceeding garment weight, lifecycle impact may exceed replacement with local secondhand. Calculate: If Total CPW after repair > Replacement CPW and fabric integrity low, replace with better construction and aim for 200+ wears. That is true slow fashion math, not just mending everything.
Frequently Asked Questions
How much should repair cost before I replace?
If repair cost >50% of replacement and future wears <30, replace. If repair cost <30% and future wears >60, repair almost always wins on CPW.
Can I repair seam slippage?
No lasting fix. Slippage is weave failure. Binding can reinforce but gaps return. Past 3mm daylight, replace or repurpose.
Is it worth repairing cheap garments?
If fabric Grade 4+ and recovery >95% and you wear it weekly, yes. CPW math does not care about original price, only future wears.
What repairs last longest?
Seam restitching with core-spun polyester 4-5 stitches/cm, waistband curtain replacement, patch + darn on wool with matching yarn, bar-tack reinforcement. Avoid iron-on patches on wool – they trap moisture.
