Decoarative fence

[Alex Horvath]

I need to make a decorative fence similar to that shown below. I believe this is 2"x6" rails/stiles on edge.

For the 1"x6" fence boards in the center, should I do a lap joint on the fence boards to accommodate expansion/contraction?
I can't do over under as done with fencing because then my fence boards would be the same thickness as the rails/stiles.

Other details planned are rails/stiles dadoed to accommodate fence boards and lattice.
Mortise and tenon joint on 2x6's.

I don't think there are any more lumber yards that sell dry redwood in my area anymore but I can probably wait for it to air dry.
Based on some fencing I recently did I believe a wet 1"x6" or 1"x8" will shrink at least 1/2" from wet to dry.
Thanks

[Jim Breen (NY)]

I made a similar fence using western red cedar. For the field of the fence, I used T&G which turned out for the better as when the wood shrunk, it still held together whereas I think shiplap may be subject to in/out movement.

Make accommodations for the stiles to expand/shrink, and don't go for a flush fit where it meets the top rail. I didn't.

[Jerry Miner]

If you want to build the fence like furniture, you could T&G the boards, or spline them (and avoid losing width), but it's a fence. Normally, fence boards are just butted together and, yes, they dry out, creating gaps between the boards. Half laps ("shiplap") could indeed be used to block one's view between boards.

The down-side of dadoing the rails for fence boards is the creation of a "water trap" on the top of the rail, leading to premature rot and failure of the structure. You might consider a detail like one of these:

349233

[Jim Breen (NY)]

I like that third option for the bottom. On mine, I used the first with weep holes (it was for my in-laws and they moved two years later, so no feedback on longevity).