National Portable Storage Association

Storage types

Portable storage containers

A portable storage container is a steel box delivered to your site so you can store goods on your own schedule. NPSA member companies rent and sell them in lengths from 5 ft to 53 ft. Use one for a move, a remodel, a job site, or extra business storage.

Modified storage containers on display at the 2026 NPSA trade show
Quick facts from NPSA members
Standard lengths
5 ft, 10 ft, 15 ft, 20 ft, 22 ft, 25 ft, 35 ft, 40 ft, 45 ft, and 53ft
Sides
12 and 14 gauge corrugated steel
Frame
Steel framing
Floor
1 1/8'' thick marine plywood
Doors
Cargo doors on one end of the container

What sizes do portable storage containers come in?

NPSA members offer portable storage containers in standard lengths of 5 ft, 10 ft, 15 ft, 20 ft, 22 ft, 25 ft, 35 ft, 40 ft, 45 ft, and 53ft. See container sizes and dimensions for floor space and door openings, or what size container you need for a quick pick.

What are portable storage containers made of?

Every portable storage container or shipping container is made from cor-ten steel. Corten steel (COR-TEN®) is a type of weathering steel that resists corrosion and typically exhibits a 50 ksi minimum yield strength. Corten steel has become the standard for shipping containers, steel bridges, and buildings that are exposed to a marine environment. Since every shipping container is built to withstand the very harshest conditions on the open ocean and in the container yard, they easily protect your valuable items. Every storage container is secure, durable, and strong.

How is a portable storage container built?

Portable storage containers are constructed with 12 and 14 gauge corrugated steel sides, steel framing, and 1 1/8’’ thick marine plywood floors. Standard storage containers come with cargo doors on one end of the container. The cargo doors seal tight from rodents and inclement weather. They also allow you to access the entire end of the container when fully open, making loading and unloading very large items a breeze.

How to get a quote

NPSA is a trade association. Its member companies rent and sell these containers. Send a quote request and it goes to member companies near you, or search the member directory yourself.

Questions

Storage containers: common questions

What sizes do portable storage containers come in?

NPSA members offer standard lengths of 5 ft, 10 ft, 15 ft, 20 ft, 22 ft, 25 ft, 35 ft, 40 ft, 45 ft, and 53 ft. Each member company stocks its own mix of sizes. Ask the member near you which lengths are available for delivery to your address.

What are portable storage containers made of?

They have 12 and 14 gauge corrugated steel sides, steel framing, and 1 1/8 inch thick marine plywood floors. The steel is cor-ten, a weathering steel. Construction can differ by unit, so confirm the build with your provider.

How do the doors work on a portable storage container?

Standard storage containers have cargo doors on one end. When the doors are fully open, you can reach the entire end of the container. That makes it easier to load and unload very large items. The doors seal tight against rodents and bad weather.

Should I rent or buy a portable storage container?

Rent for a move, a remodel, or a short project. Buy when you need storage for years or plan to modify the unit. NPSA member companies rent and sell, so you can compare both options from the same request. Our rent or buy guide walks through the trade-offs.

What is the difference between a portable storage container and a shipping container?

For storage, they are the same steel box, built to handle harsh conditions at sea and in the yard. Some mobile self-storage units are built differently, with composite panels and a lighter roof.

Need storage?

Get quotes from NPSA member companies

Tell us what you need and where. A member company that serves your area will contact you.

For the industry

Grow your portable storage business with NPSA

Members get event rates, the Community Forum, the directory listing and leads from this website.