An investigation of foaming polymer compositions containing coal tar pitch and inorganic fillers was performed to evaluate their properties and the effect of pitch introduction on fire protection efficiency. The physicochemical and technological properties of the developed materials were studied and compared with a commercially available weather-resistant, solvent-borne epoxy composition. It was found that the addition of 10% w/w coal tar pitch does not reduce the thermo-oxidative stability of the epoxy compositions and has virtually no effect on the amount of coke residue; these parameters remained comparable to those of a pitch-free sample. At the same time, the pitch-modified composition exhibits a pronounced swelling effect, with an average swelling ratio of at least 22.7. Exposure of the material to an open flame results in the formation of an intumescent char with a well-developed porous structure. This char layer subsequently undergoes partial degradation (cracking) and oxidation, leading to a progressive increase in the burnt-out area. The degradation mechanism is governed by the char’s microstructure, which consists of a mixture of large and small, predominantly open, cells. This morphology reduces the material's thermal insulation capacity by facilitating oxygen diffusion to the reaction zones and accelerating heat transfer. Nevertheless, the coal tar pitch-based composition maintains a fire resistance rating of at least 60 minutes under laboratory conditions. These results identify coal tar pitch as a promising modifier for intumescent epoxy systems; it significantly enhances fire retardancy by ensuring pronounced expansion without complicating the manufacturing process. The practical viability of using coal tar pitch is further underscored by its status as a carbon-rich industrial byproduct with currently limited high-value applications.

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