Fencing
Board-on-board vs side-by-side
What is the difference between board-on-board and side-by-side fence?
Side-by-side sets pickets edge to edge; board-on-board overlaps them. Overlapping costs more in material and is the only one of the two that stays private once the wood dries out.
Wood shrinks. Plan for it.
Cedar arrives with moisture in it and loses that moisture over the first year. Every picket gets narrower. That is not a defect and no supplier can prevent it.
On a side-by-side fence, that shrinkage turns into gaps. Pickets that met perfectly on install day are a quarter inch apart by the next summer, and you can see through your privacy fence.
What the overlap buys
Board-on-board runs a second layer of pickets over the seams. When the boards shrink, the overlap absorbs the movement and the sightline stays closed.
It also looks deeper. The shadow line between layers gives the fence dimension instead of reading as a flat wall of wood.
The honest trade
Board-on-board uses meaningfully more cedar, and that shows in the price. Side-by-side is a legitimate choice for a boundary marker or a fence you expect to replace.
For a privacy fence you want to keep, the overlap is the feature you are actually buying.
You bought privacy. Don't pay for it in a material that shrinks away from it.