A new material made of zirconium oxide fibers with silicon carbide powder as a thermal radiation absorber has been proposed, providing a reduction in the heat transfer coefficient at high temperatures. The low weight and low thickness of the thermal insulation layer allow the design of high temperature furnaces with reduced weight and external dimensions, which reduces heat losses both during furnace warm-up and in steady-state mode. The low weight of the lined material significantly reduces its cost while guaranteeing durability of continuous operation at furnace temperatures of 1800 oC for 500 days. A method of calculating the furnace in the design of lining, taking into account the dependence of the coefficient of thermal conductivity on temperature in the form of a polynomial of the fifth degree. The paper proposes a method of cal-culation of high-temperature chamber furnaces, taking into account the dependence of heat transfer coefficients on tempera-ture in the form of a fifth degree polynomial, which contains six unknown constants to be determined in a special installa-tion. The description of high-temperature such installation and the values of the coefficients of the heat transfer coefficient polynomial of a new designed fiber material with improved characteristics are given.