If you plan on cutting the window frame into a used shipping container and the container walls have and dents or repaired damage you'll quickly find out that most solutions don't work properly. In one project a client welded sections of angle iron directly into the cut out, and found that on any repaired section it was difficult to create a frame square enough to seal tightly.

The solution for installing consistently tight window frames is using a prebuilt steel frame. Steel frames can be made on site, but the manual labor involved can consume a lot of valuable time when compared to the associated costs. Purchasing a package of several prebuilt window frames will allow you to cut the holes in advance, and weld the frame directly into the space required. Once the frame is welded in the window can be set in place with sealant, and self-tapping screws.

Wall sections can be just as tricky to build and install as windows, especially if they include a door frame. No matter if its purpose is to create a two unit storage container or separate office space from tool storage, the end goal is a tight fitting wall panel and a square door that seals tight and blocks drafts and dust. Wooden frames built on site can shift during transportation and damage any finish work, or worse knock the door out of square.

The way to manage against transportation damage is to build a steel frame and install aluminium 2x4's every 18 inches. This will provide the same benefits of a standard frame, but the strength of the steel frame and light weight advantages of aluminium internal framing.

Just as with the window frames, wall sections can be produced on site, but the time and cost involved can push the final price of the container conversion up much higher, and squeeze out any margin while it happens. Prebuilt wall sections can be installed quickly and shimmed into place to provide a high quality, extremely durable wall.