Hlau thiab ntoo hluav taws qhov rooj feem ntau yog ua los ntawm ob-txheej ntoo boards them nrog galvanized hlau los xij, los yog ob-txheej ntoo boards nrog gypsum board ntawm ib sab thiab them nrog hlau los xij. Hlau thiab ntoo hluav taws qhov rooj yog sib npaug rau kev sib txuas ntawm qhov zoo ntawm cov qhov rooj hluav taws kub thiab cov qhov rooj ntoo, thiab cov ntaub ntawv refractory kuj siv rau hauv cov khoom siv kho vajtse.