Top 3 Packing Materials to Pair with Heat Packs

Heat packs are only as effective as the packing materials around them. Whether shipping reptiles, tropical fish, plants, or meal kits, combining UniHeat packs with the right insulation and buffers ensures steady warmth and reduces risk of overheating or cold shock. Here are the top three packing materials every shipper should use.

1. Styrofoam Liners

Styrofoam is the gold standard for insulation. It creates a controlled environment inside your shipping box, reducing temperature swings. Heat packs placed in a styrofoam-lined box can maintain consistent warmth for their full rated duration. Most live animal and perishable shippers rely on ¾” to 1” thick styrofoam liners for maximum stability.

2. Kraft Paper or Newspaper Buffers

Kraft paper and newspaper act as protective barriers between heat packs and the items being shipped. They prevent direct contact, disperse heat, and add a cushion against shifting. They’re inexpensive, biodegradable, and highly effective. For meal kits and plants, wrapping sensitive items in paper before placing them near a heat pack adds an extra layer of protection.

3. Insulated Bubble Wrap

Insulated bubble wrap combines cushioning with reflective thermal protection. When lining the inside of a box or wrapping around containers, it reflects heat back inside while providing shock absorption. This is especially useful for shipping delicate perishables, bakery goods, or temperature-sensitive components in meal kits.

Choosing the Right Heat Pack Duration

Pairing the correct insulation with the right UniHeat pack ensures optimal results:

40 Hour Pack

Best for overnight or 1-day shipments.

72 Hour Pack

Perfect for 2–3 day regional or cross-country shipping.

96 Hour Pack

Ideal for long-haul or cold-weather shipments.

Sampler Bundle

Test all durations to refine your SOPs.

Frequently Asked Questions

Can I use only bubble wrap without styrofoam?

No. Bubble wrap adds cushioning but does not insulate as effectively as styrofoam. Pair both for best results.

Is kraft paper enough to protect shipments?

Kraft paper is an excellent buffer but should be combined with rigid insulation like styrofoam for temperature control.

Which material gives the best thermal stability?

Styrofoam is the most reliable insulator, especially when paired with UniHeat packs and buffering layers.

Do I need vent holes in insulated boxes?

Yes. Small vent holes allow oxygen flow for heat packs to function. Too much airflow, however, can shorten duration.

Can I reuse packing materials?

Yes. Styrofoam liners, bubble wrap, and cardboard dividers can often be reused if undamaged, lowering costs and waste.