Methods for treating panels are described that include coating a wood substrate with a polymeric solution, curing the coated wood substrate by subjecting the coated wood to ultraviolet radiation and causing the polymeric solution to crosslink to produce a fire-resistant veneer. Also described is a composite material comprising a wood substrate layer, and a UV-cured flame retardant coating the wood substrate layer, wherein the composite material has a Flame Spread Index values within 0 to 25 and a Smoke Developed Index of 450 or lower.