In this study we evaluated the combustion properties of laminated veneer lumber (LVL) panels treated with various fire retardant chemicals. Commercially manufactured rotary-cut beech wood (Fagus orientalis L.) veneers were treated with a borax-boric acid mixture, monoammonium phosphate or diammonium phosphate. Based on our results the lowest combustion temperatures were observed in panels treated with diammonium phosphate (220 degrees C), while the highest combustion temperatures were observed in panels treated with a borax-boric acid mixture (420 degrees C). Chemically treated panels experienced less mass loss than untreated panels. Chemically treated panels could be used safely in building construction due to their improved fire performance.