Pre-Washing and Fabric Preparation Before Sewing
Pre-washing determines whether your finished product fits correctly after the customer's first wash. Natural fibers shrink 3–8% in their first wash-and-dry cycle — cutting patterns from unwashed fabric transfers that shrinkage to the finished product. Whether you need to pre-wash depends on one thing: whether your fabric has already been industrially pre-washed before it shipped to you.
The Pre-Wash Decision: Two Categories of Fabric
Ready-AbZORB™ fabrics have been through AKAS Tex's proprietary industrial pre-wash process before shipment. They arrive dimensionally stable with full absorbency activated — no prep washing required before cutting. Residual shrinkage is 1–3%.
Untreated natural fiber fabrics — any cotton, bamboo, or wool that has not received Ready-AbZORB treatment — will shrink significantly in their first wash. These must be pre-washed before cutting patterns.
Synthetic and performance fabrics (polyester-based) are dimensionally stable and do not require pre-washing for sizing purposes.
Check your fabric's product page to confirm whether Ready-AbZORB treatment is included.
Hygiene wash exception: Even Ready-AbZORB fabrics benefit from a single hygiene wash before use in skin-contact products — cloth diapers, menstrual pads, incontinence products, baby items. This removes handling and machine residues from manufacturing and shipping. It is not a prep wash for absorbency or shrinkage — one wash is sufficient.
Shrinkage Reference by Fiber Type
Shrinkage varies by fiber. These are typical ranges under standard wash-and-dry conditions. Results may vary based on water temperature, drying method, and specific fabric construction. All figures may vary ±10% due to textile manufacturing standards.
| Fiber Type | Untreated Shrinkage | With Ready-AbZORB | Pre-Wash Required? |
| Organic Cotton | 3–5% | 1–3% | Yes (untreated) / No (Ready-AbZORB) |
| Bamboo Viscose | 3–6% | 1–3% | Yes (untreated) / No (Ready-AbZORB) |
| Merino Wool | Variable | N/A | Yes — cool water only |
| Polyester / Performance | 0–2% | N/A | Optional |
| PUL (all variants) | Minimal | N/A | Optional — hygiene wash only |
How to Pre-Wash Correctly
The method matters. An incorrectly done pre-wash leaves residual shrinkage in the fabric.
- Wash the full yardage — not sample cuts. Small cuts give inaccurate shrinkage data.
- Match the end-use conditions — wash and dry at the same temperature and method the finished product will experience in regular use. Pre-washing cooler than end-use temperature leaves incomplete shrinkage.
- Measure before and after — mark a reference square before washing and measure again after drying. If shrinkage hasn't stabilized, run a second cycle.
- Cut from dry fabric only — damp fabric stretches slightly under cutting tension and distorts pattern accuracy.
For detergent selection during pre-washing, see General Care Principles. For drying temperature limits by fabric type, see CA-04: Drying Methods by Fabric Type.
If You Cannot Pre-Wash
Add the expected shrinkage percentage to both length and width of your pattern pieces before cutting.
Limitation: Shrinkage varies between batches and is not always uniform across length and width. Mathematical adjustment is a fallback — pre-washing is always more reliable.