When installing boards wider than 85mm we try to secrete nail first with the gun, this works if the boards are nice and stright, the floor pulls togerther neat, but if the boards are not stright, (this can occur from being stacked on site incorreclty), we use a floor clamp or chesile to pull the boards together.
Once a section of floor is installed we run a chalk line down the joists and then top nail down the line so that the nails are stright and neat.
I have sacked guys because they did not top nail before going home at night, it is the kind of thing i have bad dreams over, a floor poping and moving, 6in floors will move more than 4in as the board moves across its width, the wider the board the more possible movement.
Also dont use std liquid nails, build bond or any other ridged setting construction adhsive, and when top nailing use either "T" nails or ND brads. not "C" series
Its upto you, listen if you want but give Boral a ring on Monday monring and ask them the question.
The timber floor industry is full of a lot of crap tradesmen and flooring shops, i am not saying i am the best, but after writting almost 20,000 word thesis on it, and working in the industry i do have some small idea,
You can download the draft Aust Std from www.timber.net.au which has a table regard board widths and fixing methods.
The company that Trevor runs is one of the leaders in dry hardwood products and has been in the business for a long time, if you listen to any one you should listen to him.Quote:
Regards, Trevor
Grafton.
Quality control technician.
Kiln drying Manager.
Dry products supervisor.
Timber floor inspector.
Australian Hardwood timber flooring manufacturer.