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Craig D Peltier
09-14-2008, 12:07 PM
If I use ( I did for 10 foot fence) 4x4 cedar post will thye rot? Will thye rot just from the cement or only the dirt. My dad thinks the cement will rot them as well. I was hoping just to not let dirt hit them.
Also dont pressure treated post come in stained instead of green for purposes of fence?

Matt Ocel
09-14-2008, 12:18 PM
They will rot. Either way. You may be able to slow the rot by treating them with a petrolium product before sinking them into the ground.

If you use treated make sure it is made for Below Ground (BG) and not Above Ground (AG) applications.

I'm not sure about the stained posts, although I do recall seeing brown pressure treated material a few years back, but can't say I have seen it recently.

Anthony Anderson
09-14-2008, 12:46 PM
If I use ( I did for 10 foot fence) 4x4 cedar post will thye rot? Will thye rot just from the cement or only the dirt. My dad thinks the cement will rot them as well. I was hoping just to not let dirt hit them.
Also dont pressure treated post come in stained instead of green for purposes of fence?


In the Midwest, Menards has pressure treated with a "Cedar Tone" color. Looks pretty good, better than green pressure treated. Not sure if it is rated for underground. Bill

Craig D Peltier
09-14-2008, 12:52 PM
They will rot. Either way. You may be able to slow the rot by treating them with a petrolium product before sinking them into the ground.

If you use treated make sure it is made for Below Ground (BG) and not Above Ground (AG) applications.

I'm not sure about the stained posts, although I do recall seeing brown pressure treated material a few years back, but can't say I have seen it recently.

Hope I gte a few years out of them anyways then. Thanks

James Ashburn
09-14-2008, 2:10 PM
You need sand/gravel at the bottom of the hole to allow water to drain from the post regardless of if you use concrete or dirt. The water is what causes the wood to rot. Dry posts don't rot. Also, do not seal the bottoms of the post with anything. You can treat with a preservative but the water still needs to get out.

James

Craig D Peltier
09-14-2008, 3:51 PM
You need sand/gravel at the bottom of the hole to allow water to drain from the post regardless of if you use concrete or dirt. The water is what causes the wood to rot. Dry posts don't rot. Also, do not seal the bottoms of the post with anything. You can treat with a preservative but the water still needs to get out.

James

I pour one bag on gravel at the bottom of my holes, but the quikrete I use, the instructions for post holes are :
Fill hole with water till a few inches off of top then pour in dry concrete and then fill till the top of concrete. It sets in 20 minutes.

Ben Davis
09-14-2008, 10:51 PM
You're fine with the ceder.

Dig hole.
Fill with 4-6" of gravel.
Put post in hole.
Pour in concrete.
Add water to get the right consistency.
Level post.

I've never poured in water before adding the concrete, but my water table is so high that it would never work anyway.

David G Baker
09-14-2008, 11:34 PM
I don't add water, I add the 4" to 6" of gravel, set in the post and pour in a couple of bags of post Quickcrete. I do dig a hole wide enough to accommodate the second bag of Quickcrete and taper the hole so it is wider at the bottom than it is at the top. I have removed some of my posts and the concrete is solid and adhered tightly to the post. The Quikcrete pulls enough moisture from my soil to work well. The more moisture the weaker the concrete is what I have read.

Pat Germain
09-15-2008, 11:31 AM
FWIW, I installed several cedar fence posts about seven years ago and they're still rock-solid. They are buried in Quick-Crete. Keep in mind, Colorado Springs is pretty dry.

Roger Bell
09-15-2008, 10:39 PM
In PNW climate conditions, I would expect perhaps 15 years out of the cedar, maximum, regardless. 10 for sure. Most likely not 20. Depends more on the character of the individual stick than on most of the other factors.

For longer life look around for a treated 4x4 factory treated to a 0.40 retention treated by the incise method in a color that suits you. The retention specification will be indicated on the tag or stamped on the stick. In the PNW these will likely be hemlock or whitewood in species as they accept and hold the treatment chemicals better. You can paint or stain treated wood once it is fully dry. Hand treating, such as the various brush-on applications, is of limited utility below ground.

It is not the water that causes rotting, but the cyclical wetting and then drying and then wetting and then drying. This allows the fungi that thrive in this environment to feed upon the wood, resulting in rot. This cannot be avoided in the PNW, given the climate and the resulting ground conditions.

Wood kept uniformly wet, such as submerged in a bog, can last nearly forever as can wood kept uniformly dry, such as the wood artifacts found in the Egyptian tombs.

Chris Padilla
09-16-2008, 11:37 AM
The simple fact is:

Keep wood out of the ground, and it'll last a long time. I recently redid a fence with my neighbor and we poured a concrete footer/curb to raise the posts off the ground. We then embedded Simpson post holders into the concrete and then bolted the fence posts to the post holders. On top of that, we used 6x6s instead of 4x4s and they were pressure-treated. The 6x6 PT were reddish in color and, for a while, went nicely with the fresh redwood fence, which is now golden, and will soon be ash grey....

We fully expect this fence to outlast both of us! :)

Craig D Peltier
09-16-2008, 12:14 PM
The simple fact is:

Keep wood out of the ground, and it'll last a long time. I recently redid a fence with my neighbor and we poured a concrete footer/curb to raise the posts off the ground. We then embedded Simpson post holders into the concrete and then bolted the fence posts to the post holders. On top of that, we used 6x6s instead of 4x4s and they were pressure-treated. The 6x6 PT were reddish in color and, for a while, went nicely with the fresh redwood fence, which is now golden, and will soon be ash grey....

We fully expect this fence to outlast both of us! :)

Sound slike it will last a very long time! Was it a house line fence or to keep people put a museum or such.
I always use CWF in clear to keep fence treated and looking new.It wont fade, must apply about every 2-3 years. My dadu used to use it on our log cabin worked great there too. Back then he used to be able to spray it out of a pump spray gun ( for chemicals) but now he says the formula is too thick.

David G Baker
09-16-2008, 12:42 PM
I have used 8 foot 1 1/2" galvanized pipe with a top plate welded on and a lower plate welded on to hold the horizontal 2x4's then set the pipe in cement. If the pipe is new it should last a lifetime.

Chris Padilla
09-16-2008, 2:45 PM
Sound slike it will last a very long time! Was it a house line fence

It split our property lines, side by side. I used to have a small "ditch" along the fence that was a pain as I wheeled things along the sidewalk on the side of my hosue. With the new fence, we filled all that in thereby expanding the sidewalk a good 8". It is very nice now.