I am going to install a hardwood floor. My existing floor consists of 3/4 particle board nailed to the joists. The new flooring is 5/8" x 4" bamboo planks that can be either nailed or glued. I know that neither glue nor nails are acceptable on particle board, so these are my questions: Can I nail a 1/4 plywood underlayment over the particleboard? If so am I limited to glueing or can I then nail the hardwood floors down. Also, if I can use 1/4" plywood, should I screw it to the particle board, use ring nails that to all the way to the joists, or use any other fastening technique to ensure the plywood is firmly secures. Thanks for all replies!!!!