Overlay Flooring - Board Direction

[vincentvega]

The upper level of my house has pine T&G floorboards. These are too thin to sand again so i am going to install 13mm board over the top. The plan is to rough sand the pine floor to remove the old coating then glue and secret nail the new boards.

My question is which direction should i lay the boards? A flooring guy told me to lay in the same direction as the original boards so they expand in the same direction. my builder on the other hand wants to lay the new boards perpendicular to theold ones for strength.

Anyon have any advice?

[Gaza]

100% trowel glue direction does not matter, make sure old floor has crap loads of nails it and does not move at all

[METRIX]

We would lay them perpendicular to the old boards, but I can see the reasoning for doing them the same direction.

[shanetorque]

As I far as I know, the reasoning given for laying in the same direction above is the exact reason not to. If that makes sense.

If the pine expands and contracts at a different rate to overlay it will cause dramas.

Secondly there is no such thing as 'enough nails' so it doesn't move.

Yes to heaps of glue (actully the correct amount is better than over doing it) as IMO it's always best method to glue AND nail.

If you have to run it in the same direction for visual reasons, I'd lay a thin ply or hardboard first, then the overlay.

[Renovator22]

I Second shanes comments.
Except i would be laying a thin ply substrate even if running opposite direction say 3mm just so that you can brace it all together.
Also helps with nailing as you can nail anywhere you like when laying the ply. More nails stronger the brace/bond.