Measurement Guide
How to Measure for Walk-In Cooler Strip Curtains
Getting the measurement right before you order avoids the most common installation problems — strips too short, too few strips, wrong mounting position. Takes 5 minutes with a tape measure.
What You'll Need
- A tape measure (25-foot is ideal for larger walk-in doorways)
- Paper and pen to record measurements
- Photos of the door frame and existing mounting hardware if replacing current strips
- Optional: photos of the current strip condition to share with Cal Gaskets for a quote
5 Measurements to Take
Take these five measurements and you will have everything needed to order or quote a replacement installation.
Door opening width
Measure the clear opening width at the widest point — typically at floor level. Do not measure the door panel itself; measure the hole the door closes over. Record in inches. This is your coverage width.
Door opening height
Measure from the floor to the top of the door opening. Strip curtains should reach the floor or within ½ inch of it to maintain an effective thermal barrier. Record in inches.
Mounting bar position
If replacing existing strips, note where the mounting bar sits — inside the frame, outside the frame, or mounted to the ceiling above the doorway. The strip length is measured from the bottom of the mounting bar to the floor, not from the top of the door frame.
Existing strip width
If replacing, measure the width of one of your current strips. Standard commercial is 8 inches; some older or smaller installations use 4-inch or 6-inch strips. Matching the existing width simplifies the hardware.
Door clearance above the opening
Check how much space exists above the door opening for the mounting bar if there is no existing hardware. You need a minimum of 3–4 inches for a standard bracket. Less space may require a ceiling-mount or flush-mount bracket.
If you text photos of the doorway and the existing hardware to (707) 843-4041, Cal Gaskets can often confirm the right spec from photos before the site visit.
How to Calculate the Number of Strips You Need
The formula accounts for the 50% overlap that every properly installed strip curtain system requires:
(Door width in inches ÷ strip width in inches) × 1.5 = strip count (round up)
Example: 48" wide doorway ÷ 8" strips × 1.5 = 9 strips
The 1.5 multiplier accounts for the 50% overlap — each strip covers 4 additional inches beyond its own width. That overlap is what creates the thermal seal. Without it, cold air escapes between strips every time anyone walks through.
Common Door Widths — Strip Count at 8" Width with 50% Overlap
| Door Opening Width | Strips Required (8" ribbed, 50% overlap) |
|---|---|
| 30" | 6 strips |
| 36" | 7 strips |
| 42" | 8 strips |
| 48" | 9 strips |
| 60" | 12 strips |
| 72" | 14 strips |
The 3 Most Common Strip Curtain Measurement Mistakes
Measuring the door, not the opening
The clear opening is always smaller than the door panel. Measure the hole the door seals over — not the door itself. This is especially important for walk-in coolers where the door frame adds several inches on each side.
Forgetting the mounting bar drop
If the mounting bar is installed 6 inches above the door opening, the strips need to be 6 inches longer than the opening height to still reach the floor. Measure from the bottom of the bar to the floor — not from the top of the door frame.
Ordering too few strips
When in doubt, go up by one strip. A single extra strip costs a few dollars. A gap between strips where cold air escapes all day costs far more. Always round up on strip count.
Strip Curtain Measurement FAQs
How do I measure for replacement strip curtains on a walk-in cooler?
Measure the clear door opening width and height (not the door panel itself). Divide the width by your strip width (usually 8 inches) and multiply by 1.5 for 50% overlap to get your strip count. Note the mounting bar position — strips should reach the floor or within half an inch of it. If you're replacing existing strips, measure one of the old strips for width and thickness.
How long should walk-in cooler strip curtains be?
Strip curtains should reach the floor or within ½ inch of it to create an effective thermal barrier. Measure from the bottom of the mounting bar (not the top of the door frame) to the floor. If the mounting bar sits above the door opening, that distance adds to the required strip length.
Can I replace just one damaged strip on my walk-in cooler curtain?
Yes — individual strips can be replaced without replacing the full set, as long as the mounting hardware is in good condition and the replacement strip matches the existing width and thickness. That said, if multiple strips are yellowed, brittle, or torn, replacing the full set usually makes more sense than patching one at a time.
Not sure about your measurements? Text us a photo.
Cal Gaskets measures and installs across Northern California. If you send us a photo of the doorway and the mounting hardware, we can often confirm the right spec before even scheduling a site visit.