A density controlled cold fusion concrete cementitious spray applied fireproofing material including a mixture of water, one or more of silicon dioxide, expanded glass, vermiculite, bottom ash, perlite, expanded shale, or other lightweight aggregates of various diameter sizes ranging from about 0.025 mm to about 12.5 mm in diameter; anhydrous or hydrous sodium or potassium metasilicate; waste from steel production consisting of Granulated Ground Blast Furnace Slag (GGBFS); high calcium or low calcium waste from coal combustion (fly ash or bottom ash); sodium tetraborate, sodium citrate dihydrate, citric acid, or boric acid; and an alkali-resistant micro-.