Mesa (DM45). insulated metal wall panels are another economical choice for exterior walls and interior walls and ceilings of cold storage facilities. The Mesa (DM45). panel is our widest cold storage panel and features monolithic tongue and groove joinery for fast, easy installation. This panel is available in thicknesses up to 6”, offering superior thermal performance for cold storage buildings. Panels are embossed and lightly planked providing a uniform exterior wall aesthetic. In addition, panels are available in lengths up to 50 feet long which can minimize panel end joint conditions and improve installation time.