The door is one of the most critical components of walk in coolers and freezers. It’s also one of the most abused, getting yanked on, banged into, and subjected to environmental factors multiple times per day. And because it’s the part that interacts most with external conditions, a damaged or worn-out door may fail to seal properly, causing:
- Increased energy usage to combat warm air entering the unit.
- Condensation buildup where warm air from the outside meets cold air inside.
- Ice formation on doors, coils, and floors when condensation freezes.
- Safety risks, including slip hazards and frozen-shut doors.
- Higher strain on systems, which can reduce the useable life of other components.
“Band-aid” repairs on worn-out doors, such as swapping gaskets, will often be followed by a cascade of other needed fixes, such as replacing hinges, handles, and more. In many cases, replacing the door is the most effective long-term solution and can significantly improve the performance of your walk in for a fraction of the cost of a full replacement.
This handy guide will walk you through how to properly spec an ultra-efficient Polar Guard replacement door from industry leader Polar King, showing why each step matters.
Not sure if it’s time for a replacement? Check out this overview of Polar Guard replacement doors to find out when upgrading your walk in door is the right move and what performance improvements you can expect.
Step 1: Select whether you need a walk in cooler door or walk in freezer door
Cooler and freezer doors are built differently, and making the right choice here will ensure that your door will meet the requirements of your application. This choice affects:
- Door construction
- Hardware requirements
- Whether door heaters are required
Freezer doors experience extreme temperature differentials that create condensation that can freeze on interior surfaces and prevent doors from opening. To prevent this, freezer doors have built-in heater systems to stop ice from forming. Cooler doors, operating around 34–35°F, don’t face the same risks and typically don’t require heaters.
Step 2: Flush-mount vs. offset/inset doors
Polar King replacement doors for coolers and freezers are available in both flush-mount and offset/inset configurations:
- Flush-mount doors sit even with the wall surface
- Offset/inset doors install into the opening
There’s no performance advantage to either option. Your choice should be determined primarily by what your existing opening allows and how much wall modification you’re willing to do. Offset/inset doors are often faster and easier to install because they require less framing work.
Step 3: Measure the opening
There’s a reason for the old adage, “Measure twice, cut once.” Incorrect measurements are the most common and costly mistake in construction, and measuring for a replacement freezer door or cooler door is no exception. Precise measurements make all the difference here. You’ll need to measure:
- Outside frame (A): Stand outside of the walk in, facing the door. Measure the linear distance from one side of the frame exterior to the other.
- Inside frame (B): Stand inside the walk in, face the interior, and measure the narrowest interior width. Do not include the frame.
- Door height (C): While inside, measure only the interior door height. Do not include the door frame.
- Hinge orientation (D): Specify left-hinge or right-hinge based on the existing configuration.
- Wall thickness (E): Open the door and measure only the wall thickness of the walk in panel. Don’t include the door frame.
A door built to incorrect measurements will either be too large, which may require cutting into the walk in and increasing the complexity of labor and installation, or too small, which may not seal properly and lead to air leaks, condensation, and ice buildup.
Common measurement mistakes to avoid
Even small measurement errors when ordering a walk in cooler or freezer door can create major installation headaches and long-term performance issues. Taking accurate measurements and following the provided instructions closely will help ensure your replacement door fits properly and performs as intended. Common mistakes include:
- Ordering a door that’s too large. If your measurements are too large, the replacement door may not fit within the existing opening. Accommodating a larger door would require cutting a larger hole in your walk in, which adds to the labor, installation time, and overall complexity of the project. What should have been a straightforward replacement can quickly turn into a more involved structural modification.
- Ordering a door that’s too small. If the replacement door is undersized, it won’t seal properly against the frame. Even small gaps can allow warm air and moisture to enter the walk in, leading to condensation, ice buildup, and energy loss. This compromises the efficiency of your walk in and places additional strain on its refrigeration unit.
- Measuring the wrong distances. One of the most common mistakes is including or excluding the wrong components when measuring. For example, measuring the frame instead of the opening (or vice versa) can result in a replacement door that’s too large. Always follow the measurement instructions provided to ensure each dimension measured is the correct one.
- Failing to double-check measurements. Even experienced installers can make mistakes when measuring manually. Verifying each dimension before ordering helps prevent delays, additional labor, and avoidable installation issues.
Accurate measurements ensure your new door installs easily, seals properly, and provides the highest level of energy efficiency and performance for your operation.
Step 4: Identify nearby obstructions
Before ordering, check for anything within 8 inches of the door that could obstruct or be adversely affected by the door opening, such as:
- Light switches
- Thermostats
- Venting
- Tables or equipment
Identifying these obstructions early prevents surprises during installation.
Step 5: Choose the right replacement walk in door frame option
Polar King offers multiple frame configurations to accommodate different wall thicknesses, finishes, and preferences. All options provide the same performance. Your choice mainly affects the installation method and interior appearance.
Choose from the following:
- Outside face frame. This configuration only provides a finished frame on the exterior side of the walk in. The face frame overlaps the wall opening and creates a clean, finished exterior appearance, but the edge of the wall opening is still visible from the interior. This option is commonly used when interior appearance is less critical or when an existing interior trim is already in place.
- Outside face frame with back plate. This option keeps the exterior face frame and adds a finished trim plate on the interior side. Together, the exterior face frame and interior back plate trim the opening from both sides, integrating the insulated wall panel edge with the opening.
- “L” fit face frame. The “L” fit face frame includes an exterior face frame plus a continuous jamb that covers the interior edge of the opening. This provides a more integrated, built-in appearance and fully conceals the wall opening edge from view on one side.
- “L” fit face frame with back plate. This option provides the most fully finished appearance, which includes the exterior face frame, a continuous center jamb, and an interior back plate. Together, these components cover the wall opening from all visible angles. This configuration is typically chosen when interior appearance or symmetry are especially important.
All configurations properly seal and secure the door. The differences affect trim coverage and appearance, not insulation performance or door efficiency. The best option for your situation depends on the thickness of your existing wall and your aesthetic preferences.
The middle jamb of “L” fit frames can become quite large with walls that are 5” or more. For this reason, you may prefer to have exterior face frames and back plates instead of “L” fit frames if your walk in has thicker walls. Every installation is different — which is why Polar King builds each door to order with flexible options rather than a one-size-fits-all solution.
Step 6: Select optional performance & safety upgrades
Our walk in doors don’t require anything additional in order to provide excellent performance, but some applications may benefit from the following options:
- Viewport windows: Have staff members continually moving in and out of your walk in? You can avoid congestion and collisions by allowing them to see into the walk in before entering.
- Kick plates: You can protect your new walk in door from carts, pallets, and daily abuse in fast-moving environments with steel diamond tread kick plates.
Summary: How to spec a replacement walk in door
Spec’ing a replacement walk in cooler or freezer door should be fairly straightforward. At a high level, the process comes down to five essential steps:
- Select whether you need a walk in cooler door or walk in freezer door.
- Confirm whether you want your door flush mounted or offset/inset.
- Take precise opening measurements, including width, height, hinge orientation, and wall thickness.
- Identify any nearby obstructions that could affect installation
- Select the appropriate freezer door kit or cooler door frame configuration based on wall thickness and preference.
Getting these details right ensures your replacement door seals properly, installs smoothly, and delivers long-term energy efficiency and safety.
Polar King’s Fiberglass Advantage
Instead of steel-framed construction that allows thermal bridging and foamed-in insulation that can leave unprotected voids, Polar King’s Polar Guard replacement doors feature rigid polyisocyanurate foam core encapsulated in smooth, durable fiberglass. This allows our doors to provide top performance and lasting durability. And the smooth, seamless surface doesn’t have any crevices where bacteria can accumulate. Plus our replacement doors come pre-attached to the frame for easy installation on arrival.
Need help measuring, selecting options, or reviewing your order form? Give us a shout. We’re happy to help you make sure your replacement door is made to your exact needs.
Frequently Asked Questions (FAQs) about replacement walk in cooler and walk in freezer doors
Can I reuse my existing hardware when ordering a replacement door?
In most cases, it’s better to replace the entire door assembly than reuse existing hardware. Worn hinges, latches, and closers can compromise sealing and alignment. Polar King replacement doors include all of the hardware you need to ensure proper performance.
What happens if my replacement door measurements are incorrect?
If your door is too large, it may require enlarging the hole in your walk in, which would increase labor and installation complexity. If your door is too small, it may not seal properly, which can cause air leaks, condensation, and ice buildup.
What is included in a Polar Guard freezer door kit?
Each freezer door kit ships with the door and frame pre-attached, along with new hinges, latches, handles, and door closers. Heater systems are integrated where required, and the unit arrives ready to install.
Can replacement doors for coolers be installed without a contractor?
Most customers choose to hire a contractor for convenience, to ensure precise measurements, and to deal with any obstructions or complexities during installation. But because our doors ship with frames pre-attached and include all mounting hardware, knowledgeable end users should be able to handle the job.
Why choose a fiberglass door instead of steel for a walk in cooler or freezer?
Fiberglass doors are highly dent-resistant and won’t rust or corrode, making them ideal for humid or high-moisture environments. They’re lighter than steel, easier to operate, and hold up well under washdowns or heavy use, helping your walk in maintain a clean, professional look with less maintenance.
