Dynamical properties (compressional velocity (Vp), shear velocity (Vs) Poisson ratio (mi), shear modulus (G), and modulus of elasticity (E), bulk modulus (B), Acoustic impedance (Z), and attenuation coefficient ( ) were calculated for EP/ laminate, and chopped rock wool composites without and with immersion in water for 15,30, and 45 days at room temperature. Results of Vp, Vs, mi, G, E, Z, and of EP/laminate, chopped rock wool composite without immersion in water had obtained.