Where can I get the timber?

[Kenneth Hedlund]

I also include a picture of the fence for the curious one the gaps between the boards, which can already be sensed, are likely to increase as the boards dry.

 

[jonne72]

Have you covered with boards on both sides of the posts? If so, you could have placed the boards on each side with a half board height offset from the start and the problem would have been solved.
I don't think putting those small thin battens over all the gaps will look good at all.
I also don't generally think it's a good idea to put "caps" on horizontal lumber.

 

[Kenneth Hedlund]

Have you covered with boards on both sides of the posts? In that case, you could have placed the boards on each side with a half board height offset from the beginning, and the problem would have been solved.
I don't think putting those small thin battens over all the gaps would look nice at all.
I also don't generally think it's a good idea to put "caps" on horizontal timber.

Yes, covered with boards on both sides, but not with an offset

Starting to regret the whole build, should have gone with regular exterior panels with chamfered edge, like on the house.

The easiest now is probably, 22x45... Then I'll have to saw it myself.

 

[Holmspel]

Have you joined all the boards? If so, the gap should be very small and the only reasonable thing if you don't want any gap is to remove all the boards and set them as the tip above.

Unscrewing and redoing it is at most 3 evenings of work, right?
Chasing small strips and cutting other things takes much longer.

 

[richardtenggren]

You could have put something like windproof paper before installing the decking?

 

[jonne72]

Stuck with boards on both sides, the visibility must be minimal anyway. You'd have to stand and peek between the cracks if you want to see something. Let it be for a couple of weeks and maybe you'll get used to it...

 

[AndersS]

Apologies, but I can't resist this tip. Fill with foam insulation between the boards, it also dampens sound