How do i prepare wood post for fence

EFTHIM

I am putting a 5/4 x 6 x 8 rail fence in my yard. I will probably buy pt wood at home center. Many times wood is "wet". Should i allow posts and rails to dry more before installing? question two: should i prepare the buried portion of the posts with tar? thanks for help.

Tomboy123

When I put in my fence I just used pressure treated posts and they lasted about 20 years before they rotted out and our soil is mostly clay. It doesn't matter if they are wet or dry when you put them in but put some stones in the hole before you plant the post for drainage. I didn't concrete them in since they were just for "pretty", but I've had another PT post concreted in my back yard for 17 years and it's showing no sign of rotting so far.

cortell

I wouldn't worry about letting them dry out. Typically, such precautions are used to mitigate the effects of shrinkage. In a fence application, shrinkage is hardly a concern. In applications with lower tolerances, yes.

As for tar on the post, I've heard of people doing that. I don't bother. I take three measures to avoid post rot:

1. pour several inches of pea gravel at the base of the footing
2. use sonotube and cut it to four inches above grade (six if you're extra cautious, but it becomes a bigger eye sore the higher you go)
3. shape the top of the concrete footing in a dome shape to prevent water pooling

With these precautions, I have enough faith in the PT lumber...at least for a fence post. As for tar, I've always wondered what happens when moisture at the base spreads to the buried part of the post. Does it then get trapped by the tar as it tries to dry outwards? Sounds like a possibility to me. Thus I avoid it.