A method for the modification of wood materials to improve mechanical properties, water resistance and flame retardancy by utilizing a combination of mineralization with infusion and polymerization of biopolymers comprising steps performed in the following specific order: (i) preparing and pre-treating wood materials, (ii) hardening the pre-treated wood boards via the creation and deposition of mineral crystal or metal oxide inside the wood fiber, (iii) washing with water and drying to a moisture content below 20%, (iv) treating the wood for flame resistance, (v) treating the wood for water resistance, (vi) immersing with the first salt solution, and (vii) drying the treated wood board increasing waterproof and fireproof to a moisture content of 10%±2% to obtain the modified wood.
