Dealing with condensation in shipping containers and freight containers: Advanced remedies for moisture

What causes shipping or freight container condensation?

Condensation is the process by which water vapor in the air changes into liquid.

First let's look at what causes condensation in Ocean & Sea Containers. Condensation is caused by the temperature difference between inside and outside the shipping container in combination with humidity inside the container reaching dew point at which point gas turns to liquid.  The dew mostly forms in the top few inches of the side wall and runs down the walls.

Condensation control is achieved by either dehumidification or ventilation.  A simple way to reduce condensation is to limit the humidity inside the container before you close it up. See my other article here: condensation in containers. If you are serious about reducing condensation, storing moisture sensitive goods or even thinking of living in your container consider the following:

• Lining the container
• Painting the container a reflective colour
• Adding ventilation
• Using products like damp removal sticks

Lining your Sea Container

You can line the inside of the container with polystyrene and seal it up melamine or hardboard.

Painting your Ocean Container a reflective colour.

Make sure you paint your container a light colour to increase reflection / reduce condensation.  You can also spray the inside with a thermal insulation paint.  You only need to cover the inside of the roof and 8 inches or so down the wall.

Adding ventilation to a transport container.

When adding ventilation it is also important that the container is loaded to allow air circulation.  Place any ventilation high up in the container and make sure there is some protection for infestation such as hornets and water will not run inside.  There are various types and styles of ventilation products available.  These sea container vents fit flush in the corrugation and come complete with a screen to prevent insects and rodents.

Using damp removal sticks or other products

Damp removal sticks and other products are available to remedy condensation and moisture problems in confined spaces.  There are a number of commercial products on the market.  Damp removal poles hang on the container wall, top half contains chemicals to absorb water and the bottom half is a reservoir for excess water that slowly seeps down and collects in the bottom.  You can empty the reservoir as necessary and exchange damp sticks every 3 months or so.