Laying dry decking boards?

[Villläramer]

Hi, my decking boards have been lying loose on the deck's framework since last August, my question is whether I can screw them down now as they are or if I should wet them down? They are to be fastened with hidden screws from K-Rauta that provide a 2 mm gap between the boards (PROF system, one side at a time).

 

[z_bumbi]

Isn't it easier to increase the spacing so you get the board "width" plus 2 mm, for example, 28x120 becomes 122 edge to edge? But ask where you bought the items so they can answer on how exactly their system is meant to be used.

 

[Villläramer]

Wouldn't it be easier to increase the spacing so you get the board "width" plus 2 mm, e.g., 28x120 becomes 122 edge to edge? But ask where you bought the materials so they can tell you how their system is intended to be used.

Thanks for the reply, yes the idea is to have 2 mm between each board, but I'm not sure if it's okay to screw the boards down like that when they've been loose for so long and dried out.

 

[sinuslinus]

Thanks for the answer, yes the idea is to have a 2 mm gap between each board but I'm not sure if it's okay to screw the boards in place after they've been lying loose for so long and dried out.

The point was not to lay them with a 2 mm gap. If you measure your decking boards, they're probably 117 mm for example and not 120 mm.

 

[Alexn72]

I had measured the board. Then put a piece in water for a week, then you know.

 

[Daniel 109]

When they are dry, you need to place them at a specific edge-to-edge distance. Not with a 2mm gap. It's too little with dry decking.
That's how Svenskt trä recommends doing it regardless. See table 3
https://www.svenskttra.se/siteassets/5-publikationer/pdfer/montering-av-trall-2021-publikation.pdf

 

[Plupp 405730]

The recommendation for 120mm decking pressure-treated decking is 126mm edge to edge, if you go with 122mm when they are dry, they will swell and become tightly sealed in the fall and the wet period.

 

[Villläramer]

When they are dry, you need to place them at a specific edge-to-edge distance. Not with a 2mm gap. It is too little with dry decking.
This is how Svenskt trä recommends to do it anyway. See table 3
[link]

Thanks for the info about the spacing. So I can screw them down when they are dry with a 6 mm gap without the screws breaking when the decking boards get wet and swell?

 

[Villläramer]

The recommendation for 120mm decking pressure-treated decking is 126mm edge to edge. If you use 122mm when they are dry, they will swell and become completely tight by autumn and the wet period.

Thank you for the answer, it will be 6 mm.