cold storage sandwich panel

Client called me three years ago. Brand new freezer facility. Compressors running blind, zero shutoff. Ice thick on the interior walls. Utility overhead bleeding him dry. The diagnosis was simple. Catastrophically underspecified panels. Wrong core. Inadequate thickness. Panel spec dictates compressor lifespan. Period. +5°C to +10°C: Chillers and Produce Baseline cooling. 75mm to 100mm panels. PU core functions perfectly here. 0.022–0.024 W/m·K thermal conductivity. Do not drop below 75mm. Efficiency falls flat. 0°C to -5°C: Chiller Rooms Phase change territory. Moisture becomes frost. 100mm is the strict minimum. Protect the thermal barrier. PU remains acceptable. -5°C to -18°C: Freezer Rooms Frozen protein. Seafood. Ice cream. 120mm to 150mm required. Switch to PIR immediately. 0.018–0.020 W/m·K. PU loses cost-efficiency here. 24/7 refrigeration cycles demand PIR density. Energy savings recover the upgrade cost fast. -18°C to -25°C: Deep Freezers Long-term bulk storage. 150mm baseline. Zero exceptions. High-risk facilities push directly to 180mm. EPS is permanently disqualified. -25°C to -40°C: Blast Freezers Vaccines. High-end aquatic products. Rapid temperature drops. 150mm to 200mm. Breaching -40°C pushes requirements to 250mm. PIR strictly mandatory. No alternative cores survive this thermal shock. Envelope integrity matters. Condensation destroys steel. Z100 galvanization rusts out under heavy washdowns. Specify Z150 minimum. Coastal exposure? Z275. Joint configuration is critical. Tongue-and-groove edges. Heavy sealant application. Micro-leaks destroy cooling efficiency. At Propanel (propaneltech.com), we match core, thickness, and steel gauge directly to your operating temperatures. Eliminate specification errors. Protect the compressors.

I learn a big lesson few years ago. One customer call me and complain about his new freezer warehouse. His compressor machine run 24 hours non stop, ice everywhere on the wall, and his electric bill is crazy high! What is the problem? Because he buy cheap panel not for -20 degree! Wrong core and wrong thickness. That day teach me one thing: in cold storage, sandwich panel is not just normal building material. It is your money!   So what is really good for cold room? Core is number one. PIR is the smartest choice for freezer. Thermal conductivity only 0.018 to 0.020. This is the best insulation! It mean your cooling machine can rest. If you only do cooler at 2 to 5 degree, PU is ok (0.022 to 0.024). If you have normal dry warehouse next to cold room, use EPS to save budget. But if you have strict fire rule? You must buy Rock wool, Class A1 non-combustible. Fire cannot burn it. But thermal number is higher (0.038 to 0.040), so you must buy thicker panel.   Thickness is also super important. For 5 degree cooler, 75mm panel is enough. But if you do -18 degree for frozen meat or ice cream? You must use at least 120mm PIR. Go down to -30 degree deep freezer, then 150mm or 200mm is the only choice. If panel too thin, your compressor cry and run everyday. If too thick, you waste money for nothing. Just choose correct thickness by your temperature.   Also do not forget panel joint! Cold air always try to leak out from small hole. Good cold room panel must have cam lock and tongue-and-groove edge, so they pull very tight together. And sealant glue must be good for low temperature, normal glue will crack when it freeze. Outer steel skin is key too. You need check zinc coating, at least Z100. If your project near sea water, must use Z275 to stop rust. Moisture will always find unprotected place and destroy the steel!