Concrete around fence posts?

in some soils the concrete holds the moisture in the wood post , a well drained option like tamped limestone allows the post to dry

if it is dry all the time the post stays dry even in the concrete

the life of concreted wood posts will vary widely from location to location

but generally a tamped post will last as long or longer than a cemented post in the same soil , but the concrete costs you more , so why not use cheap road stone and tamp

decks are governed by a different set of rules you have to do what is code , but they also generally are mowed around and in better drained areas , also under a deck they stay a lot drier than in a field

posts in a pole barn will last a very long time as they stay dry under the cover of the roof

We have had to use quikrete around some posts due to not being able to dig deep enough (3 feet) we could only go down 2 feet till solid rock, then jack hammered to 2 1/2. DH was done after that last 6 inches... We use hedge posts so they don't ever really rot. At least not in our life time! I've still got post around that my grandfather put in! lol. The trick is to de-bark them. (at least the part that will go in the ground). If they rot in the next 50+ years, I'll let you all know.

When I do fencing all my corners are in concrete, using a form will last longer. Then the corners are braced. I usually let it stand for a week then run fence.

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Since so many people are talking about cement rotting posts, this weekend I walked the fence line on my grandmother's farm. I installed all of the posts with quikrete in 1980 or 81. Some of the posts are somewhat rotted on the top. A few are showing some grit wear at ground level, but are not rotted there....even in swampy areas. Some of the posts have heaved significantly. All posts were set with dry quikrete and tamped.

I've heard a lot of talk about cement rotting treated posts, but have never experienced it. I HAVE seen this on untreated posts.

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It just depends. I have seen it happen on treated split rail where the all the posts that were set in dry concrete concrete broke off at ground level after a few years but the ones not set were fine and dandy. I think it does depend on the post because I have seen 4x4 treated wood last forever set in concrete as well. I am wondering if it also has to do with how green the wood is when it was set, whether or not it is treated. When I work with 4x4's, I like to leave them setting around for months to dry first because they tend to be so wet when you buy them these days. They get so much lighter to work with when I do that.

Our extension agent recommends against cement for posts. Recommends tamping them in in layers with a mix of gracel and dirt. Here's a good pub on fences.http://extension.uga.edu/publication...m?number=B1192

...........Some additional points , (1)A post with it's base covered in cement is a Stronger post because that solid bloc of concrete will be much harder to move when horizontial forces try to displace the soil it is anchored in !
...........(2)'Tamping' maybe considered 'Better' , because it adds a longer lifespan to each post , But it certainly isn't any 'Better' from a structural point of view .
...........(3)All things considered , used oil field welded Sch. 40 pipe is the strongest type of post one can build a fence out of ! Used telephone poles come in second behind steel pipe , but access to used Tpoles is limited and they are usually more expensive that pipe on a per foot basis . , fordy

Just expanded our deck in 2013. We used sonotubes filled with wet concrete and inserted J bolts in the top. Once the concrete cured, we mounted metal brackets that hold the 6x6s on the J bolts. We used the heavy-duty ones that cost a lot more (but add peace of mind!). The brackets are designed with a 1" offset to keep the bottom of the timbers dry. No worries about rot, and a LOT easier to get the posts lined up and plumb.