Moving an art piece over a body of water is as much a technical problem as a logistical one. For art professionals, like museum registrars, gallery owners, or collectors, the real enemy is not just the distance but the variability of the environment.

When a package goes from a climate-controlled gallery space to a cargo ship or an airport tarmac, it undergoes a “thermal shock," where temperature fluctuations can cause oil paint to crack, wood to warp, and adhesives to break down.

To reduce these risks, the best art shippers focus on producing a “micro-climate,” an environment that doesn’t change even when conditions outside the container fluctuate. Here are a couple of smart ways professionals use to create that environment and protect art pieces during overseas shipments.

Passive Thermal Shielding and Reflective Insulation

Traditional steel containers used for shipping are notorious for having the “greenhouse effect,” where the temperature inside the container can be higher than the outside air, especially when sitting on a sunny dock. To counter this, several tricks are used to insulate the containers and control the rate of thermal exchange.

One common option is to use thermal blankets for shipping containers. Unlike reefer containers that may fail or run out of fuel, these heavy-duty thermal blankets offer a reliable layer of protection. Most of these blankets have aluminum linings capable of deflecting up to 97% of radiant heat. By placing these blankets over palletized crates or against the walls of the containers, the shipper can create a buffer that keeps the temperature within a narrow, safe variance.

This method is necessary because it solves the dew point problem as well. The thing is, the temperatures inside a container drop rapidly at night, leading to “container rain,” which can ruin any work of art. Top art shippers understand these issues and use thermal barriers to ensure that the temperature change from day to night is gradual, not quickly, so that the substrate of the art piece doesn’t get ruined in the process.

Museum-Grade Double-Wall Crating with Vapor Barriers

While regular containers provide the outer shell, the real protection comes from the crate itself, which helps create the micro-climate needed during transit. However, a simple wooden box just won’t do, especially for high-value overseas transits. That’s when experienced shippers resort to a double-walled crating system, or a box within a box, separated by a high-density archival foam.

These measures are essential to absorb the physical shock and add a thermal layer for added protection. The inside of the crate is often lined with a polyethylene vapor barrier, also referred to as “silver bag,” which is heat-sealed to the artwork to ensure no air enters or leaves. It also protects the artwork from the humidity in the shipping container, which is vital during sea freight, where the air is salty and humid.

Interestingly, some professionals try to achieve better results by “preconditioning” the crate. This is done by leaving the crate and the packing materials in the gallery’s climate-controlled environment for at least 48 hours before sealing. This helps bring the air trapped inside the vapor barrier to the same humidity and temperature that the artwork was originally exposed to. Once sealed, the inner environment stays the same because of the double-wall construction.

Endnote

Creating a micro-climate for artwork transportation is vital and often involves building layers of redundancy. That’s what professional shippers achieve through options like airtight vapor barriers, high-reflectivity materials, and even precise humidity buffers. Be sure to check how the shipper is going to handle the artwork before you decide to deliver it across continents.