Subscribe or Renew Membership Subscribe Renew

Fence Post Rot in Concrete Prevention question

gregorykouretas's picture

Fence post typically rot near the ground, i believe because the repeated wet dry cycle. I have read if using concrete to slope it away from the post and above grade, so this is what i have done. (Actually a 6x6 free standing pergola post i am building, but same concept)


Here is my idea. Does anyone think it would help if i used a product like drylock on the concrete to stop the post from the wet dry cycle near ground level? Will the drylock waterproof the top portion of the post or will it do the opposite and hold the moisture in. How often would this need to be applied outside? Every year? What are everyones thoughts?


Also if it does rot, how long does do you think i can get out of a 6x6 pressure treated post? i am never going to be able to dig up the post which is 4 feet deep wiht concrete so am hoping it last a good 30 years?

fence post rot (post #207797, reply #1 of 4)

Yes it happens right at ground level where there's moisture, a food source and oxygen. What I've been doing for quite awhile is slope the concrete away like you say, then wrap the base with copper which as it oxidizes, kills the rot and mold below.

Thanks for the advise, how (post #207797, reply #2 of 4)

Thanks for the advise, how would i make a copper band, and how do i attach it? Nails Caulk?  What about copper roof flashing, would that work?

copper (post #207797, reply #4 of 4)

I go to a local sheet metail place, they usually have alot of scrap copper flashing. I have them cut it into 2 1/2" wide strips, then I fasten with small copper brad nails.

The best solution is to not (post #207797, reply #3 of 4)

The best solution is to not use concrete around the post.  Use crushed rock instead.

Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville