Construction having integral circulatory system

In combination, (A) a cryogenic liquid storage vessel comprising a load-bearing wall, a primary barrier layer of impermeable polyurethane foam, a circulatory system disposed therebetween defined by a network of cells having side walls which are generally in lateral orientation to the primary barrier layer and the load-bearing wall, at least some of said side walls having apertures therein thereby providing means whereby each cell is in communication with at least one adjacent cell in a manner defining a continuous controlled circulatory path passing through each cell of said network, and a secondary barrier layer of impermeable polyurethane foam partially filling the cells in the region between the apertures and adjacent the load-bearing wall, and (B) means for circulating a fluid through said circulatory system.