No, but that does not mean that mold cannot grow on the surface of the plastic spray foam insulation. Building materials, when installed to create a building envelope assembly, work interactively as a system, to control the movement of heat, air, and moisture.
When not properly designed or installed, moisture can move through the building envelope and condense on cold surfaces that are below the dew point temperature or create high levels of moisture. This moisture, at certain temperatures, in the presence of organic food sources (paper, wood, bacterial dust, etc.) can provide the conditions necessary to promote the growth of mold and mildew. While Spray Foam is not a source of food for mold, mildew or bacteria, organic specks of dust can collect on the surface of the foam. In combination with moisture at the right temperatures, these organic specks of dust can result in mold and mildew. Spray Foam, like all insulation products, can result in mold and mildew problems in building envelopes that are poorly designed or constructed. Proper air sealing, as well as use and placement of vapor retarders and sufficient levels of insulation, are key to proper building envelope design.