Robert A. Volz is credited with discovering the first process for making reticulated polyurethane foam in 1956 while working for the Scott Paper Company. Production of reticulated polyurethane foam is a two-step process that begins with the creation of conventional (closed-cell) polyurethane foam, after which cell faces (or "windows") are removed. To do so, the fact that the higher surface area and lower mass of cell faces compared with cell struts (or edges) makes them much more susceptible to both combustion and chemical degradation is exploited. Thus, closed-cell foam is either filled with a combustible gas like hydrogen and ignited under controlled conditions, or it is exposed to a sodium hydroxide solution to chemically degrade the foam, which will remove cell windows whilst sparing the edges.  
Reticulated ceramic foams are made by coating a reticulated polyurethane foam with an aqueous suspension of a ceramic powder then heating the material to first evaporate the water then fuse the ceramic particles and finally to burn off the organic polymer.
Reticulated metal foam can also be made using polyurethane foam as a template similar to its use in ceramic foams. Metals can be vapor deposited onto the polyurethane foam and then the organic polymer burned off.