Long story short, I am building approx. a 6x12 pergola in my yard. On the 6 foot sides (the 2 ends) I was going to attach 2 horizontal 4x6 beams, one upper and one lower, to the 6x6 upright posts. I am then going to put lattice on the ends framed in between the posts and the horizontal beams. It will be for climbing plants.
The question I have is, will a 4x6 spanning 6 feet be sufficient to not sag over time?
The drawing shows the horizontal beams as 4x4 (I did this Sketchup a while ago). Since then I have decided to make them 4x6's to "match up" with the 6x6 posts. I was going to position the horizontal beams so if you were facing it, the 3-1/2" dimension would be vertical and the 5-1/2" dimension would be horizontal. In other words, the horizontal beam would be flush to the 6x6's on the front and back. There would be no reveal.
The question I have is, will a 4x6 spanning 6 feet be sufficient to not sag over time?
The drawing shows the horizontal beams as 4x4 (I did this Sketchup a while ago). Since then I have decided to make them 4x6's to "match up" with the 6x6 posts. I was going to position the horizontal beams so if you were facing it, the 3-1/2" dimension would be vertical and the 5-1/2" dimension would be horizontal. In other words, the horizontal beam would be flush to the 6x6's on the front and back. There would be no reveal.
