Estimate a walk-in cooling load
Four questions about the box gets you a rough capacity range, so you can sanity-check a quote or work out what you are dealing with before you call anyone. No email required.
Four questions about the box
Typical loads at moderate use
Figures assume an 8 ft ceiling, insulated panel construction in reasonable condition, a steady door through service and a daily mixed restock.
| Floor area | Cooler (+2 to +4 °C) | Freezer (−18 to −23 °C) |
|---|---|---|
| 40 sq ft | 2,300 – 3,200 | 4,200 – 5,700 |
| 60 sq ft | 3,500 – 4,800 | 6,300 – 8,600 |
| 80 sq ft | 4,700 – 6,300 | 8,400 – 11,400 |
| 100 sq ft | 5,900 – 7,900 | 10,600 – 14,300 |
| 150 sq ft | 8,800 – 11,900 | 15,800 – 21,400 |
| 200 sq ft | 11,700 – 15,900 | 21,100 – 28,600 |
How the estimate is made
Nothing here is hidden. The estimate starts from a load per square foot of floor at an 8 ft ceiling, then adjusts for how hard the box works.
- Cooler base: 50 BTU/h per sq ft
- Freezer base: 90 BTU/h per sq ft
- Door traffic: light ×1.00, moderate ×1.15, heavy ×1.35
- Product load: light ×1.00, moderate ×1.20, heavy ×1.45
- Shown as a range of plus or minus 15%
A full calculation adds transmission through each surface, infiltration from the actual air changes, the product pull-down, lights, fans, defrost heaters and the people working in the box, then divides by the compressor run time. That is what we do on site.
What moves the real number
- Insulation thickness, and whether the panels are still dry
- Ceiling height — these figures assume 8 ft
- Where the condensing unit sits, and how hot it gets there
- Door gaskets, closers and whether anything props the door
- Glass doors, lighting and anything else inside making heat
- How fast you need warm product pulled down
Want the real number?
Tell us the box, what goes in it and where the unit would sit. We will work it out properly and tell you what it takes.