Shipping Container: Insulating the Bottom Rail

Insulating the Bottom Rail of a Shipping Container


Section 1

Option 1 Insulating the Bottom Rail;

Insulating the Bottom Rail of a Shipping Container

Insulating the bottom rail of a container presents a unique challenge because the rail is perpendicular to the shipping container's corrugated side walls. InSoFast CX Container Panel are designed for the side walls of most shipping containers. In this video above Ed explains a novel approach to filling in a hidden airspace at the bottom rail with reverse cutting of the CX Panel.

Cut a CX44 panel to fit into the rail;

Cut a CX44 panel to fit into the rail.

At a table saw dado a cut into the panel deep enough to encapsulate the top of the rail  into the CX 44 panel. You may need to cut the face off of the fill in piece to fit snuggly and full support the full panel with the dado cut.

Additional modification to the panel may be neccessary. Here we removed a 1/2" square to fit over square tube corner.

Finished Detail

Option 2 Insulating the Bottom Rail;

Option 2 Insulating the Bottom Rail

This approach works well  and it is a little bit more robust of a detail with the 2 by lumber providing a harder impact surface. This detail is better suited for reatail rental fleets.

Adhesively apply a filler insulation panel that will give you a flush finished surface.

Mechanically attach the 2 by material through the foam and into the bottom rail.

Detail Cross Section;

Finished Detail Cross Section


The Recommended Adhesive:


Section 1

1. Why Use Loctite PL Premium 3x;

Loctite PL Premium

LOCTITE® PL PREMIUM® POLYURETHANE CONSTRUCTION ADHESIVE

New Look Buy Shipping Container Insulation Panels in Monroe, NC

Green Guard Certified Adhesive:

One of the many reasons we recommend Loctite PL Premium is it has the GREENGUARD Certification.  It is important to us that you use an adhesive that has low chemical emissions, you are building in an airtight shipping container, improving the quality of the air you breath is kind of important.

InSoFast panels were designed with simplicity in mind and we would argue that gluing them is not only the easiest method of installation but often the most effective. Third-party testing has shown the adhesive bond strength of our studs to have 108psi of holding power. This means each adhered panel is capable of holding over 5,000lbs!

In Canada the Glue is LePage PL Premium

Testing was conducted using Loctite PL Premium’s 3X Stronger Construction Adhesive, (in Canada it is marketed under the LePage PL Premium brand,) on clean concrete surfaces. It is the only adhesive we have tested. Other formulas and brands may not work as expected.

2. Estimating Adhesive Quantity;

Estimating Adhesive Quantity

Estimating the amount of adhesive YOU will use has variables beyond our control like condition of your walls and how accurate are you with a glue gun? The example below is for one side wall of a 20' standard height shipping container you will need approximately 3 tubes of the adhesive. That is in a perfect world. PL Premium 3x adhesive is applied in a ⅜" bead on the backside of the studs onto the ribbed surfaces.  We realize that a 3/8" bead of glue is very subjective. It is important that there is enough adhesive to squish the dovetails on the back side of the stud when pressed to the container wall. Adhesive follows the "Goldie Locks rule, too much, too little, and just right. If you are doing just right you can expect that 1 large 28-fl oz tube will cover 18 of our 24" long studs or enough glue at a 3/8" bead to cover 36 foot long bead of glue. 

Additionally you will have to estimate for glue around openings like windows and doors.

1 large 28-fl oz / 828 mL tube = 18 (24" studs or inserts)

  • CX 44 (22 panels with 2 studs each plus 8 end wall edges) = 52
  • 52 ÷ 18 = 3 tubes of the adhesive

 To verify that enough adhesive is used, press the panel into place. Pull the panel back and check to see if the adhesive has spread out beyond the full width of the stud. It is normal for the panel to "float out" from the side of the container when it is accommodating irregularities in the container walls. Additional adhesive may be necessary in some areas.

3. Adhesive Quantity Chart;
LOCTITE® PL PREMIUM® POLYURETHANE CONSTRUCTION ADHESIVE Rough estimate for  28 ounce tubes of adhesive required
Container CX 44 Side Walls End Wall and Inserts Ceiling and Inserts Swing Doors Floors Total without doors and floors Total Estimate with doors and floors
20' Container - Standard 3 Per side total 6 2 1/2  6 1/2 3 7 13 23
20' Container - High Cube 3 Per side total 7 2 1/2  6 1/2 3 7 14 24
40' Container - Standard 6 Per side total  12 2 1/2  13 3 14 28 45
40' Container - High Cube 6 Per side total  13 2 1/2  13 3 14 29 46
4. Important Notice: Container Surface Preparation, Temperature Application;

Important Notice: Container Surface Temperature Applications

When bonding EPS and XPS foam insulation, use above 40°F (4°C) and avoid cure and surface temperatures above 90°F (32°C). Surfaces must be clean, dry and free of frost, grease, dust and other contaminants. Pre-fit all materials and protect finished surfaces. If using cartridge format, cut nozzle at a 45° angle to desired bead size and puncture inner seal. Be very careful not to allow Loctite® PL® Premium to cure on a finished surface.

Cold Weather Tips:  

Interior Installation

Heating the interior of the container will not be sufficient for the adhesive to cure because the insulation panels will not allow heat to transfer to the container surface.  It is recommended to either move the container to a heated area or tent and heat the exterior until the adhesive has cured.

Exterior Installation

The interior of the container can be heated until the adhesive has cured.

Interior and Exterior Installation

Install the exterior panels first while heating the interior.  Allow adhesive to cure before installing interior insulation.

Overview / FeaturesTechnical Data / Directions

5. Safety Precautions;

Wear gloves. Cured adhesive on bare skin will not come off immediately with washing and will cause skin to darken. Cured adhesive and discoloration will come off in about 3 days.

6. Cleanup;

Clean tools and uncured adhesive residue immediately with mineral spirits in a well-ventilated area to the outdoors. Remove cured adhesive by carefully scraping with a sharp-edged tool.


Download PDF Instructions


Container installation guide pdf
Container Supplemental installation guide pdf
Insulating a shipping container door pdf

InSoFast Plus Method

Need a higher R-value? No Problem! Start with a base of InSoFast continuous insulation panels they are feature-rich and easy to install. Then add rigid foam insulation over top of InSoFast panels.