Thread: Horizontal wood fence/barrier

I've not heard of 'MLV' boards, but the only way I know of to prevent gaps is a second layer overlapping the first. In Australia that would be a pretty common boundary fence, although vertical.

Originally Posted by Cerick305

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My question is:

*What can I do to have boards tight together without them destroying each other from normal expansion/contraction. I’m in an area that can have 90% humidity one week and 50% the next..

Thanks all for your help...

Short answer is that you cannot. Timber "lives" and swells and contracts with moisture.

That expansion is a major reason why clapboards overlap each other. (Clapboards are called weather boards on this side of the Pacific.)

One solution, mentioned by Doug, is to have two layers with generous gaps between the planks and all joint staggered.

Various noise control systems are used in Australia for sound attenuation along highways. Around my neck of the woods a common timber barrier seems to be plywood panels connected along tongue and groove edges.

Sound Barrier, Sound Screening and Fencing, building supplies

If I put boards as close as possible when humidity is low and then screw them into channels. Will the boards tighten so much when humidity rises that the boards crack? Or would they just be more snug?

I reckon the boards will buckle.
The only way I could see a single layer remaining gap free would be to join them together like a giant table top, maybe dowels, and drop into the channels so the whole lot behaves like a single board. But even then, if one expands unevenly, ie bends, it will still crack. Maybe tongue and groove would work.
I think you need to allow for expansion and contraction, not try to prevent it.