Walk-in refrigerators and freezers may be pre-engineered (or prefabricated) in standard or customized sizes or built into kitchens.  They may be located inside or outside a facility, built with or without floors, and may contain in-place or remote condensers.

Most walk-in boxes, given their cold holding storage functions, are made using prefabricated panels with urethane insulation sandwiched between aluminum, stainless steel, and other “skin” materials such as high density urethane or fiberglass.  Manufacturer’s rate panel insulation with an “R-value” and most major manufacturers’ panels are rated around R-30, which requires about 4” of insulation.  Panels are also available with 5” or 6” of insulation with higher R-values.  Panels are mass-produced in standard sizes, normally 1’, 2’, and 4’ in width, and heights of 7 ½, 8 ½ and 9 ½...

Quality door designs are vital to the effective use of walk-ins, as doors receive the manumum stress during use.  Rigid, reinforced doorframes and heavy-duty hinges provide maximum durability.  Swing-out doors in widths of 24” to 34” are available and may be left- or right-hinged.  Sliding doors are also available for walk-ins.  Deadbolt locking handles are standard on many models.  Inside door releases are a standard safety feature that operators can specify as a push-bar for hands-free operation.

Walk-ins are available with self-contained refrigeration systems, in which the evaporator coil and compressor/condenser are mounted together on a frame, interconnected with pre-charged refrigeration lines and mounted on a ceiling or sidewall.

An air-circulation system that allows a walk-in to draw in cold outside air when the exterior temperature is colder than the interior box temperature is available to supplement a unit’s compressor.  Another option is a pressure relief valve designed to eliminate the slight vacuum created when warmer air enters a walk-in and expands when the door is closed, which can make it difficult for staff to open a unit.

Walk-in refrigerators and freezers are primarily used to chill or freeze and safely hold large quantities of both raw and cooked products to support daily production activities and preserve an inventory.