At Walker Rubber, we understand that not all containers are created equal. Turning a shipping container into a comfortable, liveable space takes more than cutting doors and adding windows. It requires durable and reliable sealing to keep those inside warm and dry.
That's where we helped a customer in the container conversion space recently. Whether it’s to protect an office unit from the elements, or sealing a welfare space for long-term use, our rubber container door seals are engineered to withstand and perform under even the most hostile of conditions.
This project, where we supplied an innovative company transforming old shipping containers into modern, human-centric spaces, highlights the best of Walker Rubber: our bespoke rubber manufacturing capabilities and how they make all the difference.
Who was the customer and what did they require?
Our customer is an expert in container conversions, giving new life to used shipping containers by converting them into homes, offices, and welfare units. Each project is unique and highly bespoke with custom layouts, doors, and windows designed for everyday use.
When we first connected, they were using standard container door seal profiles and ordered several samples from us to assess suitability. Pleased with the quality, they placed an order for straight lengths of EPDM rubber extrusions, which allowed them to cut and fit the seals themselves across different container builds.
However, they soon found that joining the corners of these seals is more difficult than it looked. Their mechanical joining methods - with glue - held the seals in place, but over the long-term, weren’t seamless or durable enough. They needed something stronger and more professional that could match the quality of their finished units.
What solution did Walker Rubber provide?
After detailed discussions with their production team, we proposed manufacturing custom, ready-to-install container door seal frames that matched the specific dimensions of their window and door configurations.
Rather than sending straight lengths we produced complete spliced frames using our vulcanisation process, delivering ready-made seals that could be fitted straight into the units.
This gave our customer:
- Perfectly sized seals for each container door and window type
- Zero waste from trimming and offcuts
- Faster, simpler installation
- Seamless corner joints with no weak points
What was the process?
Material: EPDM
All our container door seals and frames are manufactured from EPDM (Ethylene Propylene Diene Monomer) - a high-performance rubber designed for outdoor insurance and weather protection.
Key Benefits of EPDM:
- Weather and ozone resistance: EPDM is chemically inert and does not degrade under UV, ozone or oxidation exposure
- Long service life: It can remain on a container for 20 years or more without losing elasticity or sealing strength
- No cracking or chalking: Unlike many types of rubber, EPDM has no double carbon bonds that reacts to ozone, preventing whitening or surface cracking
- Low maintenance: Ideal for habitation units and other long-term outdoor applications where reliability is key.
Splicing and Vulcanisation
Because EPDM cannot be effectively glued - it's too chemically stable - we use a vulcanisation process known as splicing to create strong, permanent joins.
This process works by:
- Placing a Sulphur-rich strip between the ends of two EPDM sections
- Applying heat and pressure to fuse the materials together
- Forming a chemical bond that's as strong as the rubber itself
Click here to watch out splicing process in action.
Were there any challenges?
Our customer required a variety of different frame shapes and sizes, depending on the container’s configuration. Some container door seals needed to be made with three or four sides, depending on the door design.
Fortunately, with in-house tooling and splicing capabilities we were able to produce these bespoke sizes, while giving our customer a cost-effective solution.
What was the result?
The end result was a high quality, fully bespoke sealing solution that simplified our customer's workflow and elevated the finish of their conversions.
With our pre-manufactured EPDM container door seals and window seals, they achieved:
- Reliable, seamless seals with strong, waterproof joins
- Faster installation times on every build
- Zero material waste
- A cleaner, more professional finish suited to customer-facing spaces
Looking for reliable container door seals?
From standard profiles to custom EPDM frames, Walker Rubber can supply durable, weather-resistant sealing solutions tailored to your specific needs.
Our vulcanised splicing process has been proven across hundreds of bespoke frames worldwide, delivering long-lasting protection even in the most challenging outdoor environments.
If, like our customer, you’re also looking for dependable, made-to-measure container door seals or window seals for habitation or goods transportation purposes, contact us today to discuss your requirements.