Fibreboard Underlay... to tape or not to tape?

[booyaka10]

Hi all,
I'm about to start laying my first lot of laminate flooring (on a wooden subfloor), I've bought fibreboard underlay (5mm thick) for reasonable level of soundproofing.
However there seems conflicting info on how to lay the underlay... one minute I read that I need to butt the boards together and no tape leaving a 5mm gap around the perimeter of the room.
Next somewhere else I read that I need to tape the boards but leave a 5mm gap between the boards (presumably for expansion??), as well as leave a 5 mm gap around the perimeter...
Any advise on how what to do this type of underlay would be most welcome...

Many thanks!

 

[mattysupra]

no tape.
You need expansion, this can be 5mm around the edge and gaps between the boards or say 15mm around the edge and no gaps between the boards.

 

[booyaka10]

no tape.
You need expansion, this can be 5mm around the edge and gaps between the boards or say 15mm around the edge and no gaps between the boards.

Cheers for the response! Your advise is appreciated!