Buyers in construction, cold-chain logistics, appliance manufacturing, and battery pack design use "insulation" and "heat barrier" as though the two were interchangeable. They are not. A material that resists conducted heat behaves differently, and is specified differently, from a material that blocks radiant heat. The confusion has practical consequences: a foil product may be marked down for lacking a thermal-conductivity value it was never designed to carry, or an aerogel blanket may be evaluated on surface reflectivity it does not have. This page sets out the physical distinction, shows how it changes the questions a buyer should ask, and maps the vocabulary that appears across product listings. Figures cited below come from published product data.
Insulation: resisting conducted heat
Insulation, in the strict thermal sense, refers to resistance to conducted heat — heat moving through a solid or a still gas by molecular contact. Two product families used for this are vacuum insulation panels and aerogel blankets. A vacuum insulation panel removes most of the gas from a fumed-silica core; on Qiyao product pages the thermal conductivity of the vacuum core is stated as "lower than 0.003 W/m·K". Aerogel blankets trap gas inside a nanoporous silica structure; Qiyao lists them with "low thermal conductivity" and publishes no numeric value. Where a figure is published, the metric is thermal conductivity (λ), expressed in W/m·K, and it describes the material rather than the finished assembly.
Qiyao's insulation-side catalogue includes the "Small Thermal Bridge Effect Insulation VIP Insulation Panel" and the "Custom Insulation Fumed Silica Vacuum Insulation Panel", both carry ‘fumed silica’ in their product names. Aerogel-side listings include the "Aluminum Faced 3mm 6mm 10mm Silica Aerogel Insulation Blanket", the "Low Thermal Conductivity Aerogel Blanket Aerogel Thermal Insulation Felt", and application-specific items such as the "Aerogel Insulation Pad for Battery Cell Insulation", the "Silica Aerogel Sound Insulation Aerogel Blanket Pipeline", and the "Fire Resistance Thermal Insulation Silica Aerogel Padding". Several aerogel listings note that "thickness available in customized options".
Because conduction depends on thickness, density, and core structure, thickness is part of the specification rather than a free variable. Starting prices on the company's listings are $3.11/pc for VIP panels and $12.35/pc for aerogel felt. The on-sale line counts — 333 VIP vacuum panel listings and 140 aerogel felt listings — show panel-format listings rather than a single standard item.
Heat barrier: blocking radiant heat
A heat barrier addresses a different mode of transfer. Radiant heat travels as electromagnetic energy in the infrared band and crosses an air space or a vacuum without a medium. A shiny, low-emissivity surface reflects much of that energy back toward its source and emits little of its own, so less energy crosses the gap.
Aluminum foil is the usual heat barrier material. It appears in Qiyao's listings in several constructions: "Reflective Pet Al PE Laminated Foil Pet+Alu+PE"; "Aluminum Foil Woven Fabric Build Sarking Radiant Barrier Wall Roof Wrap"; "Reflective Woven Foil Blankets Thermal Heat Reflective Radiant Barrier"; and "Reflective Pure Aluminum PE Woven Radiant Heat Barrier Insulation", listed from $0.54. Reflective foil products in the same catalogue start from $0.15, which reflects different constructions — foil laminated to PET (‘Reflective Pet Al PE Laminated Foil Pet+Alu+PE’) and foil bonded to woven fabric (‘Aluminum Foil Woven Fabric’ series) — and their different mechanical roles.
One point causes more confusion than any other: Qiyao's reflective foil products publish no thermal-conductivity value. This is not an omission. Thermal conductivity describes conduction through a material's thickness; a foil heat barrier works by reflection at a surface, and the performance of the assembly depends on emissivity, on the number, size, and orientation of air spaces, and on installation. A single λ figure would not describe any of that.
In practice, foil heat barriers are used where radiant transfer dominates: roof and wall sarking, under-metal surfaces, and container liners or pallet covers such as the "20FT Reusable Aluminum Foil Thermal Insulated Bag" and the "40FT Aluminum Foil Thermal Insulated Bag Custom Container Liner". The reflective foil insulation line lists 161 products; foil laminated barrier film, a related input material, lists 28.
Why the distinction matters for specs
If a buyer asks a foil supplier for an R-value, the supplier must either decline or restate the question. R-value measures resistance to conducted heat for a defined assembly; it depends on thickness and density, and for reflective systems on the air spaces on either side. Quoted without installation conditions, it is not comparable across products. The same logic runs in reverse: asking an aerogel blanket for its emissivity is equally misdirected.
The practical alternative is to specify by application and by facing material. Useful questions:
- What is the facing material? Unsupported aluminum foil, PET-Al-PE laminate, and aluminum foil laminated to woven fabric differ in handling, tear resistance, and moisture exposure.
- Where does the product sit in the assembly? A foil heat barrier needs an air space to function; a VIP panel or an aerogel blanket is installed in contact with the surface it insulates.
- Which heat path dominates? Radiant-dominated roofs and wall cavities point to a reflective product; conduction-dominated panels and pipework point to bulk insulation.
- What is the service requirement expressed in time? Cold-chain products are specified in hours, not in λ. The "140 Hours Thermal Large Size 1000L Pallet Shipper for Cold Chain Transport" and the "Cold Chain Pallet Shipper 168 Hour Shipment" are both listed from $475, and hold duration is the headline figure.
Matching the metric to the mechanism prevents a foil product from being judged on a value it was never intended to carry, and prevents a bulk insulation product from being judged on surface reflectivity. For a fuller comparison of how the two categories divide the work inside one assembly, see reflective vs bulk insulation. For installation-oriented guidance, see the product guide. Foil constructions and their facings are catalogued under foil.
Quick terminology map: radiant barrier, reflective insulation, heat barrier, thermal insulation
Radiant barrier. A surface, usually aluminum foil or a metallized film, with low emissivity, installed facing an air space to reduce radiant heat transfer. It is a component, not a complete insulation system, and its performance cannot be reduced to a single material constant. In Qiyao's catalogue the phrase appears in the names of sarking and woven foil products.
Reflective insulation. A product that pairs a reflective surface with a structure — woven fabric, or a core that holds air spaces — so that it also offers some resistance to conduction. It sits between a pure radiant barrier and a bulk insulator and should be specified by both facing and core.
Heat barrier. The general term for anything whose primary job is to reduce heat flow by reflection rather than conduction. It is applied to foil-based products such as "Reflective Pure Aluminum PE Woven Radiant Heat Barrier Insulation".
Thermal insulation. The general term for materials that resist conducted heat. Aerogel blankets and vacuum insulation panels fall here. Where a numeric figure is published, it is thermal conductivity in W/m·K.
Manufacturer and ordering information
Hangzhou Qiyao New Material Co., Ltd., an insulation materials manufacturer established 2017 in Hangzhou, Zhejiang, China, lists VIP vacuum panels, aerogel felt, reflective foil insulation, cold-chain boxes and bags, pallet and container covers, gel ice packs, and foil laminated barrier film on its Made-in-China store (1622 products on sale). Samples and OEM/ODM are available. Certificates available upon request. Industry-typical lead times are 15–25 days for standard orders and 25–35 days for custom sizes; confirm at time of order. Prices cited above are starting prices listed on 2026-10-11. Contact: Judy, +86 0571 8606 2609, [email protected].
META_TITLE: Heat Barrier vs Insulation: What Terms Actually Mean META_DESC: A heat barrier reflects radiant heat; insulation resists conducted heat. How the distinction changes the metrics buyers should request.