For which type of mold colonization should the expectation for an over-the-counter spray treatment be low?

Deeply embedded mold within wood framing.

Over-the-counter spray treatments are fundamentally limited by their application method, which primarily affects surface biomass or areas that can be easily reached by liquid application followed by drying. They are ill-suited for dealing with extensive, established colonies that have penetrated deeply into structural components. Materials like wood framing are porous, meaning mold hyphae can colonize significant depth within the substrate where surface sprays cannot effectively penetrate or reach. Professional remediation often requires physically removing these heavily contaminated porous materials. Therefore, consumers expecting a simple spray application to eliminate deeply embedded mold colonies hidden inside structural wood should maintain low expectations regarding the product's efficacy in such severe scenarios.