How much void fill do I need?
Void fill keeps products from moving around inside the box. Too little, and items shift and break. Too much, and you're spending money filling space that shouldn't be there.
The calculation
A 12 × 10 × 8 inch box holds 960 cubic inches. An 8 × 6 × 4 inch product takes 192. That leaves 768 cubic inches, about 0.44 cubic feet, to fill.
Types of void fill
Loose fill peanuts
Good for irregular shapes and filling every gap. They settle during transit, so pack firmly and top up. Sold by the cubic foot; a 14 cu ft bag is a common size. Biodegradable starch versions are available.
Paper
Crumpled or folded kraft paper is recyclable, easy to dispense and good at blocking and bracing. It's heavier than air pillows, which can add to shipping weight.
Air pillows
Very light and quick to use from a machine. Best for filling space around durable items, less so for heavy or sharp products that can pop them.
Molded pulp and inserts
Not void fill in the usual sense, but a fitted insert replaces fill entirely and holds the product in one position.
How much space is too much?
If empty space is more than about a third of the box, the box is probably too big. Beyond filling costs, oversized boxes raise dimensional weight and look wasteful to customers. Many large retailers now require suppliers to limit empty space.
Packing it right
- Put a layer of fill in the bottom before the product.
- Center the product and fill around all sides.
- Fill to the top so the flaps close flat without bulging.
- Shake the box. If anything moves, add more.
The best fix is a better box
Every cubic inch of empty space costs fill, time and often shipping. Sizing boxes around products, with only the cushioning they need, cuts all three at once.