Insulate a sea container with the best insulation there is. The variety of projects that Polyurethane foam can be used for means our job is rarely boring. We have insulated a number of sea containers and so far, this one, is the most creative.
To capture a view
Iconic Fremantle’s Port wharf. The checkerboard stacks of constantly flowing sea containers. What a view to capture. So, when designing the extension to their home and in keeping with the theme, this creative couple chose to add a 2nd level using a Sea Container. Set in a position at the back of the block, the container faces north for the view of the harbour. Their own private vista of the Fremantle’s Port.
Steps to take
A 20” sea container was craned in over the existing home and placed on top of the new ground floor extension. Voila, a 2nd storey with a birds-eye view that is cost effective, quick and sturdy. A spiral staircase provides access from the ground floor. Double glazed windows will be installed at both ends and the container “doors” will act as protection and privacy for and from the neighbours.
Spray Foam Insulation for a Fremantle Sea Container Extension
This project used a 20-foot sea container as the second level of a creative home extension in a Fremantle port and wharf setting.
The container was craned into position and faced north to take advantage of the harbour view. Spray foam insulation was applied to the walls and ceiling, with double-glazed windows planned as part of the wider build. The original container doors also provided privacy and protection when closed.
Why Sea Containers Need Careful Insulation
A steel container reacts quickly to outdoor temperatures. Direct sun can heat the metal shell, and cooler conditions can lower the internal surface temperature just as fast.
Buildings of this type can also have limited internal space, so the insulation system needs to work within a compact structure. Openings, framing, windows, services, and the final wall lining all affect the available cavity depth.
Condensation also needs attention. When warmer air meets a colder metal surface, water can form inside the structure. The insulation, ventilation, windows, and intended use of the container should be considered together.
How Spray Foam Works in a Container
Spray foam is commonly used in containers because it follows the shape of the corrugated steel walls and ceiling. It can cover edges and irregular areas that may be difficult to fit neatly with rigid sheets or batts.
The foam also helps reduce uncontrolled air movement across the insulated area. The appropriate foam type and thickness depend on the container design, location, internal lining, and how the finished space will be used.
For more information about how the material works, visit our complete guide to spray foam insulation. Our residential insulation services also cover roof, wall, and underfloor applications.
Common Questions About Sea Container Insulation
Can spray foam be applied directly to container walls?
It can be applied to suitable prepared surfaces. The container should be assessed for corrosion, leaks, contamination, and areas requiring future access before spraying.
Does a container still need ventilation after insulation?
Yes. Insulation reduces heat transfer and air leakage, but the completed space still needs ventilation suited to its intended use.
Should windows and services be installed before spraying?
The construction sequence should be planned in advance. Window openings, electrical work, plumbing, and future linings can all affect access and application.
Planning a Container Conversion?
At Tates Coating Services, we have installed spray foam insulation across residential, commercial, industrial, and marine projects since the 1980s.
For free information, advice, or a quote for your container project, contact our team.
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