Fill Power
Fill power is an indicator of how much the down used in down products expands and recovers under specified conditions, and it is mainly used as a guide to warmth and lightness.
Contents6 sections
Definition and Overview
Fill power is an indicator of the loft of down, or its ability to trap air and expand. In general, the higher the value, the bulkier the down at the same amount, and the easier it is to achieve warmth while keeping weight low.
It is not a term that indicates interlining classification or bonding performance. If fill power is written in a context referring to interlining, confirm with the specifications or supplier whether it is a misunderstanding of down terminology or an original term.
Applications and Role
It is mainly used when evaluating the performance of feathers filled as batting in down jackets, coats, vests, bedding, and similar products. It serves to create an insulating layer by placing down between the outer fabric and lining.
In apparel, it is used for the body, sleeves, hoods, and similar parts. However, the required warmth is not determined by fill power alone. Fill amount, the ratio of down to feather, quilt design, and the wind resistance of the outer fabric also affect it.
Materials and Types
The subject of fill power is mainly down, which is the three-dimensional plumage that grows on waterfowl and has a barely visible quill. Feather is plumage with a quill, and separate from fill power, it is part of the design of mixed filling materials.
Synthetic fiber batting such as polyester also has batting for insulation, but it is not usually described by fill power. For synthetic batting, select by checking fabric weight, thickness, loft, warmth retention, and wash durability.
How to Choose and Points to Note
At the planning stage, consider the target warmth, product weight, wearing situation, and fill amount comprehensively. Even if fill power is high, warmth may be insufficient if the fill amount is small, and product cold-weather performance cannot be compared by numbers alone.
For thin or soft outer fabrics, check downproof performance to suppress feather leakage, leakage from seams, and the appearance of quilting. It is important to confirm in prototypes that the texture of the outer fabric is not impaired, while also checking the loft after filling and ease of handling during sewing.
- Check the total fill amount of the product and the allocation by part.
- Check down ratio and fill power as separate items.
- Evaluate feather leakage from the outer fabric and lining, and leakage from seams.
- Check recovery after washing or cleaning.
Notes on Bonding and Sewing
Fill power itself is not an indicator of fusible interlining bonding conditions, peel strength, or firmness. When using interlining together with down products, separately select a fusible interlining suitable for the outer fabric for the necessary areas, such as facings, plackets, and pocket openings.
In sewing, if feathers get into seam allowance or around the sewing machine, this may lead to poor seam adhesion or feather leakage. Share the order of the filling and sewing processes, quilt specifications, and seam finishing with the factory in advance.
Frequently Asked Questions
If fill power is high, is it always warm?
Not necessarily. Fill power is an indicator of down loft, and warmth is also affected by fill amount, down ratio, quilt structure, outer fabric wind resistance, and ease of movement when worn. Even with the same fill power, the feel varies depending on product design.
What is the difference between fill power and down ratio?
Fill power is an indicator of how easily down expands. Down ratio indicates the proportion of down contained in the filling material. The former concerns loft, and the latter concerns the composition of the blend; when comparing down products, check fill amount in addition to both.
Does fill power indicate the firmness of fusible interlining?
No. The firmness and finish of fusible interlining are evaluated by the type of base fabric, thickness, fabric weight, type and amount of resin applied, bonding conditions, and similar factors. Fill power is a term used mainly for the loft of down, so when selecting interlining, check the bonding conditions and stiffness.
