Shipping container ventilation

Dry cargo containers may seem like airtight steel boxes, but they’re actually designed with a hidden feature that helps protect your goods from damage: ventilation. Whether you’re storing, shipping, or converting a container — understanding how airflow works inside can save you from costly problems.

How Many Vents Does a 20'DC Container Have?

Most standard 20-foot dry containers come with 8 to 14 passive vents, depending on the model.

• Placed high near the top side rails

• Louvered or screened for weather and pest protection

• Non-mechanical — airflow happens naturally

What Do These Vents Actually Do?

Passive ventilation creates a crossflow of air:

• Fresh air enters from one side

• Warm, moist air escapes from the other

• This circulation reduces humidity buildup

It’s a simple design — no power, no fans — but it helps keep the internal climate stable.

Why Ventilation Matters

Containers exposed to sun, rain, and temperature swings risk interior damage. Without airflow, your cargo might suffer from:

• “Container rain” — condensation that drips from the ceiling

• Mold & mildew — damaging textiles, packaging, even machinery

• Unpleasant odors — from plastics, chemicals, or organics

• Rust — weakening steel parts

Want Better Airflow? Here's What You Can Do

If you're using a container long-term, upgrading ventilation is smart:

• Add extra vents near floor and ceiling

• Install roof vents for rising heat

• Use mechanical fans for active air circulation

• Consider insulation to prevent extreme temperature swings

This is especially important for workshops, storage of organic goods, or converted living spaces.

Summary

Ventilation in dry containers might be hidden — but it plays a critical role. It protects cargo, preserves container quality, and creates safer internal conditions. Whether you're shipping electronics or storing tools in your backyard, good airflow is not optional — it’s essential.