Not nailing the floor is a common problem with some floor fitters, often they may only put a few nails in per board or even only nail every other board. Saving cost is most likely their reasoning as the customer can't exactly see the difference straight away or even see the nails them selves a lot of the time as they are buried out of sight in the board.

The short fall of doing things this way is that the wood flooring will be loose, which will allow them to move around and make a lot of noise when they are walked on.

There is a flip side of this which is of course adding too many nails which can cause cracked tongues and also lead to loose floors believe it or not! This is a problem in oak flooring or any flooring for that matter. The basic rules to nailing is that there should be a minimum of two fasteners per board and that each fastener should be 1 to three inches from the end of the board for. Standards trip flooring the fastening space should be around every 8 to 10 inches and every 4 inches for plank flooring.