Floor boards are laid on 'foxtrot' board, laid over the smart ply, to help absorb the sound transfer through the floor.
Close up of the foxtrot board.
The first row of floorboard to go down along the landing - setting the line.
We choose to nail the boards down with sheradised nails rather than glue the boards down. Using glue would have reduced the sound transfer through the floor even more. However glues tend to 'off gas' and can reduce the indoor air quality.