Cold storage construction: building a warehouse that stays cold

A freezer warehouse is finished when it has held its setpoint for a week with the doors cycling and product inside, not when the last panel is set. We put that week on the schedule before we put in the first one, because a cold building that opens warm is not open. Everything about cold storage construction runs backward from that pull-down test.

The envelope is the product

A dry warehouse is a shell with things inside it. A cold storage building is the opposite: the envelope is the product and the shell is there to keep the weather off it. Walls and ceilings are insulated metal panels, thick enough for the temperature they hold, joined with gaskets and sealants that form a continuous vapor barrier on the warm side. The vapor barrier is the whole game. Warm, moist outside air that finds a path into a freezer wall condenses, freezes, and pushes the panel apart from the inside over a few winters. Every penetration, every panel joint, every place the roof meets the wall is a place the barrier can fail, and each one is detailed and inspected before it is covered.

Refrigeration belongs in the first meeting

Compressors, condensers, evaporators, controls and the refrigerant choice between ammonia, CO2 and synthetic systems decide the electrical service, the roof structure, the machine room location, and the ceiling clearances. Choosing the refrigeration contractor and the system design after the building is drawn means redrawing the building. We bring that vendor to the table at the concept stage, fix the equipment schedule early, and design the electrical and structural packages around real equipment rather than placeholders. The refrigeration scope is not a piece of equipment installed at the end; it is the reason the building exists.

What is under the freezer floor

A freezer floor sits on ground that will freeze if nothing stops it, and frozen ground heaves and breaks slabs. Under a freezer slab there is insulation, and beneath the insulation there is a heating system, glycol loops or electric cable, that keeps the subgrade above freezing for the life of the building. The slab itself has to be flat enough for high-reach forklifts, dense enough for constant temperature cycling, and jointed so that the joints do not spall under wheel traffic. None of this can be fixed after the pour. Our own concrete and excavation crews handle the subgrade, the underslab systems and the slab, and a principal is on site for each pour.

Docks, doors and temperature zones

Every dock door is a hole in the envelope. Cold storage docks use vertical-storing levelers that seal against the floor, inflatable or foam shelters that seal around the trailer, and high-speed doors that are open for seconds rather than minutes. Between the dock and the cold room there is usually a refrigerated vestibule or an air curtain, so that a trailer door opening does not dump humid air into the freezer. The site plan has to give refrigerated trailers room to stage with their units running, and the electrical plan may need reefer plugs at the dock so they can plug in.

Most facilities hold several zones: a freezer, a cooler, a dock at a mild temperature, and dry storage. Each zone needs its own refrigeration circuit, its own panel walls, and doors between zones chosen for how often they cycle. The layout should follow the product flow the tenant actually runs, and it should be decided before the panel order is placed, because moving a freezer wall after the fact means cutting panels, rerouting refrigerant lines and re-sealing the vapor barrier.

Commissioning: the week that decides turnover

Turnover of a cold building has its own checklist: the refrigeration system is started and balanced, the building is pulled down in stages so the slab and panels are not shocked, the underslab heating is verified, the doors and dock seals are tested with a thermal camera, and the space holds temperature through several door cycles. Only after that do we walk the punch list and hand over the keys. A principal of our company runs that week personally, because the day the first truck backs in is the day the owner starts earning.

Send over your program, your temperature zones and the equipment you have in mind, along with the date the first load needs to arrive, and we will build the schedule backward from the day the building holds cold.