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finallyME
03-27-2012, 12:28 PM
Hopefully this falls into homesteading. Otherwise, mods, feel free to move to the proper section.

So, I need to put up a fence around my yard. When I bought the house, the fence was blown down. We live in a pretty windy area. A lot of people who get vinyl fences end up with pieces all over the place. I was originally going to put in a wood fence with metal poles, but metal poles cost twice what a treated 4X4 costs. One of the problems with the old fence is that the posts (cedar 4X4) rotted out in the ground. I don't want that problem (one reason why I wanted to go with metal posts). So my question, what is the best way to anchor in the posts? I believe I read here that sinking them in concrete will rot them out faster. I have done posts in the past where I coat the bottoms with tar and then just sink them 2 ft in and pack the dirt around the post with a rock bar. Anyways, any advice is appreciated.

Rick
03-27-2012, 01:11 PM
I've put in a lot of cedar fence posts and I refuse to use concrete. Even for gates. You will eventually have to replace that post and then you'll have to excavate the concrete along with the post. Mine is a 3 rail split rail and if I remember correctly the posts are 6' 6". I think I put them in 27" deep, which leaves 4 feet and a couple of inches above ground. Cedar posts around here last about 10-12 years. We have a fairly high water table. You hit water about 24 inches +/-.

I dug down beside the existing posts enough to loosen them and extract them. I then slid the new posts in the hole making certain it was correct depth and no rotten wood was in it. I tamped it in with a frost bar.

crashdive123
03-27-2012, 02:09 PM
I put up a privacy fence (board on board) next door about 4 years ago. I just used 4 X 4 PT posts - no concrete - no issues. I did my back yard the same way about 15 years ago. Still going strong with no issues.

One thing I did do though was to use short galvanized deck screws to secure all of the slats. The staples that are used in the manufacturing process seem to fail rather quickly if any slats start to warp. It was a lot of screws, but it prevented "issues".

Pal334
03-27-2012, 02:45 PM
I put up a six foot "picket" type fence here about 15 years ago with 4x4 posts into the dirt, no cement or other treatment, is still as solid as ever, no signs of rot. Have replaced some of the pickets due to rot. This is a high humidity area.

Dwane Oliver
03-27-2012, 02:47 PM
We put some Cedar posts in down by the river , about 20 years ago , in cement.
The old man I was working for made me pull the first 2 out and re do them, he said we should put them in a trash bag first , that will keep the moisture out. I drove by there about a week ago , fence is still there and holding cows in.
We just put a good heavy trash bag around the postthen cemented around the trash bag , about 2' deep.
We normally dont cement posts in around here , but we couldnt get the soil to pack , as it was too wet down there. YMMV

finallyME
03-27-2012, 02:56 PM
Crash, did you just dig the hole, and then tamp the dirt around the post?

crashdive123
03-27-2012, 06:04 PM
I did. I used 10 ft posts, cut off 1 ft and used a post hole digger for a 3 ft hole. That might have been over kill, 2 ft hole would probably have been fine.

randyt
03-27-2012, 07:23 PM
I have a solid 1 1/4" steel bar about 6 foot long that I tamp with. I like old telephone poles for posts. If fancy is required I throw them on the skid way and saw them to a nominal 6 by 6 or 4 by 4. But I don't like fancy so usually they go in the ground as is.

LowKey
03-27-2012, 09:37 PM
I've done fence posts using pressure treated lumber (the good stuff, not the do-it-yourself-store stuff) with gravel at the base of the hole so the endgrain has no soil contact. Wouldn't want to seal the end grain with tar or anything that will keep water in the wood. Seems a plastic bag would do the same, keep water against the wood.
Never tried a concrete collar, mostly cuz I don't ever want to have to dig the concrete out.
I don't think I'd use pressure treated near a food garden though. I have to install a fence sometime this year in the side yard (to keep the neighbor's teenagers from parking their newly acquired cars on our land) and was considering cedar, only cuz the garden will be extended to the fence when it goes up.

COWBOYSURVIVAL
03-27-2012, 09:51 PM
All good advice! I have a alot more fence posts than I want to think about. One thing I'll add, your posts should go in upside down. A tree wicks water from the ground, you want your posts to wick water downwards, the opposite of the way a tree grows....

Rick
03-27-2012, 10:06 PM
Is there like a growth arrow that tells you which way is up?

JPGreco
03-27-2012, 10:07 PM
If its near a garden, get cedar posts. If not, treated will work. You have a couple of options. First is to just sink the 4x4s into the ground. Just make sure you get the bottom of the post at least a few inches below the frost line or your fence may heave. Your other option is to pour a concrete footing with a tiko or other brand of metal anchors and attach the 4x4 to that, which would be above ground. That's a lot of work though and costs a lot more for minimal advantage if any. DO NOT sink the 4x4 into concrete. Wood should not be in direct contact with cement. The cement will wick water into the post, which will cause it to rot faster. Probably the best way to do it would be to dig a larger hole than needed. put a few inches of gravel at the bottom, put the post in and surround it with gravel a few inches up the post, then back fill with dirt. This will allow a small area for water to drain away from the post.

LowKey
03-27-2012, 10:07 PM
My grandpa said something similar about the upside down thing. He used to make fence posts from Sassafras. If you didn't plant them upside down, often they'd root and grow.

JPGreco
03-27-2012, 10:09 PM
I also agree with the idea of screwing off the planks in stead of the the staples. That is of course if you're putting up a privacy fence. You can just go more old fashion and put up a property line fence which won't catch the wind, but will still prevent cars and animals from getting past it (though deer can jump over it).

LowKey
03-27-2012, 10:11 PM
I don't know about those above ground anchors. They aren't meant to be non-load bearing and aren't really rated for the horizontal wind load a fence will get. Even one with 50% blow-thru. Be sure to check that before shelling out the money. They're expensive.

You'd be surprised how much wind load you can get on something that has holes in it. We do staging covers using textaline mesh with as much as 70% blow-thru and still have to get an engineering stamp on the load.

I didn't say set the post in a bucket of concrete. With gravel at the bottom, there is no concrete 'bucket' to hold the water against the wood. I know guys that do them that way and they seem fine, but like I said, I don't want to have to dig it out.

Rick
03-27-2012, 10:13 PM
You boys must have a deeper water table than we have around here. If you poured gravel in the hole it would just give the water a place to collect around here. Sort of like a well.

LowKey
03-27-2012, 10:16 PM
yeah, the water table here is just about 10 feet. Or an inch above the cellar floor pad. Depending on the season.

COWBOYSURVIVAL
03-27-2012, 10:22 PM
Is there like a growth arrow that tells you which way is up?

Most of us use the the fact that the narrow end should go in the ground...But especially for you Rick, take a good look at the knots...You are good at knots anyhow, right? Your knots should be growing towards the ground....but, then yours already are are right?

Rick
03-27-2012, 10:24 PM
There must be a small spring across the street from me. My neighbor's house has a crawl space with a sump pump that runs almost all the time. I think the house must have been built on a spring. My crawlspace is dry as a bone but 10 feet away is my first fence post and I hit water at about 2 feet. We are the highest point around here so it's kinda odd. There are a lot of springs in the area, however.

Wildthang
03-28-2012, 08:47 AM
This post disturbs me, because I had a deck built onto the back of my house last spring, and the guy that built it used pressure treated supports, and poured concrete around the posts. How long does it take the posts to rot when they are installed in that fashion? They are buried 2' deep, with a 8" x 8" paver in the bottom of each hole, with Sacrete around the post!

finallyME
03-28-2012, 09:59 AM
Thanks for all the replys. I really appreciate it. It is nice to know that the better option is also the cheaper option. Now I don't have to buy a bunch of concrete, or tar. It is also faster to just dig the hole and tamp in the post, instead of pouring, waiting, making sure the post is straight while the concrete dries, etc.

Rick
03-28-2012, 11:52 AM
I would have thought he would have poured a concrete footer from below frost line to the surface then mount the 4x4 piers on that. They make a metal post base that mounts to the footer and holds the 4x4 a couple inches off the ground so it doesn't stand on wet concrete. Some are even adjustable. A little easier to change out if you have to. Here's a pic.

http://decks-ca.com/Deck_Footing_and_Piers/footing_detail_4.jpg

http://www.braunderalumber.com/images/88postbase2.gif

kyratshooter
03-28-2012, 01:59 PM
The contractor installed the deck posts just as they are recommended in this area. Lowes and HD instructions for DYI state to pour concrete partway in the hole and let set, place the posts on top of the concrete and finish filling with gravel.

I just moved from a house just south of you Ohio guys. The deck had been in place, set in concrete, for over 20 years, and it was still sound.

The back porch platform where I am now is PT/creasote dipped 6x6 set straight into the ground and it is still solid after 40 years.

I am sure posts standing in water would go pretty fast, but modern PT is done to resist insects and rot and it does so very well.

Wildthang
03-28-2012, 04:25 PM
The contractor installed the deck posts just as they are recommended in this area. Lowes and HD instructions for DYI state to pour concrete partway in the hole and let set, place the posts on top of the concrete and finish filling with gravel.

I just moved from a house just south of you Ohio guys. The deck had been in place, set in concrete, for over 20 years, and it was still sound.

The back porch platform where I am now is PT/creasote dipped 6x6 set straight into the ground and it is still solid after 40 years.

I am sure posts standing in water would go pretty fast, but modern PT is done to resist insects and rot and it does so very well.

Thanks man, it sounds like my deck will at least be around as long as I am!

JPGreco
03-28-2012, 04:57 PM
This post disturbs me, because I had a deck built onto the back of my house last spring, and the guy that built it used pressure treated supports, and poured concrete around the posts. How long does it take the posts to rot when they are installed in that fashion? They are buried 2' deep, with a 8" x 8" paver in the bottom of each hole, with Sacrete around the post!

Its recent that the no contact with wood has started. Its against code here now. It will take a long while to rot, but it will rot faster than a 4x4 on top of a footing attached with a tiko. How much faster I really don't know.

randyt
03-28-2012, 05:21 PM
pole barn poles are set on concrete in this area. A full bag of quick crete is mixed and poured in the hole. After setting up the pole is set and tamped int place.

Darkevs
04-22-2012, 01:50 PM
I have always split my own posts from cedar logs.

Yes, you do have to replace them if they rot off at the bottom, but so what. :)

I love digging fence post holes and splitting posts and rails.............great exercise. :)

Spartan300
05-27-2012, 09:20 AM
The best fence posts I have ever used are "utility poles." When fencing in a new section of field for my goats, I was able to get some poles from my local electric company, as they were replacing several in my area. The old ones were still in fine condition for getting posts from. I took my chainsaw and cut out 20 beautiful posts. They were heavy, and already treated. I simply sunk them in the ground and just added a little crusher run at the bottom of my holes for water drainage. I slightly cut the tops of the poles at an angle to let rain run off easier. What a find! Just took a little labor and time, but when I compared my poles to those at the Home Improvement Centers, there were no comparison. Best of all...they were free.

mountainmark
05-27-2012, 09:57 AM
The best fence posts I have observed are made of granite. You can walk through the woods around here and come across fences over a hundred years old. The wire has disintegrated but those fence posts are still standing true. A bit expensive, but will last a few lifetimes.

Old Professor
05-27-2012, 10:35 AM
Rick, the reason your water table is higher than your neighbor, even though your land is higher, is that the water table is not level. It more or less follows the contour of the land. Slightly deeper at high places and shallower at low places.

Rick
05-27-2012, 10:44 AM
Spartan - The old black jack poles would last nearly forever. At least the part above ground. They were treated with creosote like railroad ties so they were pretty impervious to weather. And they were pressure treated so you probably got some really good wood. The newer poles are treated with either pentachlorophenol in oil, CCA (Chromated-Copper-Arsenate) or creosote. The CCA are green in color, because of the copper. I would be a little cautious where I placed Oil treated or CCA treated posts if you have any concerns about your animals eating grass growing next to the posts or if you have a concern about garden veggies in the vicinity. Chemicals do leach. That was one of the concerns of creosote.

Back in the day you could get class ten poles from any telephone company and they were a really good size for fence posts. Today, very few use the 10 class pole any more and most utility companies are concerned about liability so the legal department has stopped donating the poles to farmers. We used to deliver them to the barn for farmers, especially if it was on their land, just as a good corporate citizen. But those days are pretty much gone unless you can find a crew that will help you out.

randyt
05-27-2012, 10:47 AM
Here in the sticks we can still get utility poles. One of these days I need to scrounge up a few.

Spartan300
05-27-2012, 10:48 AM
Spartan - The old black jack poles would last nearly forever. At least the part above ground. They were treated with creosote like railroad ties so they were pretty impervious to weather. And they were pressure treated so you probably got some really good wood. The newer poles are treated with either pentachlorophenol in oil, CCA (Chromated-Copper-Arsenate) or creosote. The CCA are green in color, because of the copper. I would be a little cautious where I placed Oil treated or CCA treated posts if you have any concerns about your animals eating grass growing next to the posts or if you have a concern about garden veggies in the vicinity. Chemicals do leach. That was one of the concerns of creosote.

Back in the day you could get class ten poles from any telephone company and they were a really good size for fence posts. Today, very few use the 10 class pole any more and most utility companies are concerned about liability so the legal department has stopped donating the poles to farmers. We used to deliver them to the barn for farmers, especially if it was on their land, just as a good corporate citizen. But those days are pretty much gone unless you can find a crew that will help you out.

Good points sir. Luckily I had a crew that helped me out. I let them park their trucks on my property a few days during the job. Never hurts to be nice...lol.

Rick
05-27-2012, 10:53 AM
That's for sure and it plays both ways. That's why we gave them the poles. I've met my share of farmers with shotguns that did not much care whether we had right of way or not. We started plowing one field where we didn't have right of way. We didn't know that at the time of course. The Right-of-Way Agent just hadn't gotton the signatures. The old boy owned a TD9, single axel truck and flatbead trailer for a few days before they got it all straightened out. I'll bet that turned out to be some mighty expensive right of way.

Cajunlady87
05-27-2012, 03:01 PM
Hopefully this falls into homesteading. Otherwise, mods, feel free to move to the proper section.

So, I need to put up a fence around my yard. When I bought the house, the fence was blown down. We live in a pretty windy area. A lot of people who get vinyl fences end up with pieces all over the place. I was originally going to put in a wood fence with metal poles, but metal poles cost twice what a treated 4X4 costs. One of the problems with the old fence is that the posts (cedar 4X4) rotted out in the ground. I don't want that problem (one reason why I wanted to go with metal posts). So my question, what is the best way to anchor in the posts? I believe I read here that sinking them in concrete will rot them out faster. I have done posts in the past where I coat the bottoms with tar and then just sink them 2 ft in and pack the dirt around the post with a rock bar. Anyways, any advice is appreciated.

I don't know what size posts, type of wood or special treating you are considering. What I can address is sinking them in concrete from my own experience.

My home was built in 1987 and elevated 12 feet. Creosote treated utility posts are what it is built on and anchored to. Eight feet of the posts were sunk, then a cement slab two feet in thickness was poured and left to set for a fairly long time. There are 36 of these utility posts supporting my home and not one is showing any signs of rotting or my home would be sinking and showing signs of being unlevel. There are many homes and fishing camps built this way in my area. Usually when a hurricane visits us and the home gets demolished, the utility poles are what remain still driven in place in the slabs. Just something else for you to consider. :)

Rick
05-27-2012, 06:16 PM
As I said above, I would never ever put a fence post in concrete. You'll have to dig it out some day because the post will rot no matter what you do. Been there, done that and learned a valuable lesson about fence posts. Homes and utility poles are one thing. Fence posts a different matter.

Desert Rat!
05-28-2012, 02:19 PM
For those that have wood fence post set into concrete already you might try this, I made a T-handle screw by welding a 1 1/4" round bar about 16" long onto a 1" x 12" long screw , drill a 1/2" hole into the broken post and screw in your T-screw, it should come out fairly easy, I've replaced a dozen or more using this method, you may have to taper the post a bit to get it into the concrete but it beats digging out the concrete, now all new fence post I've used black pipe about 1 1/2" OD set in concrete I have a section of fence 20+ years old using black pipe thats as straight now as the day I built it, now this is the Mojave Desert and the water table under my property is 100FT so I'm sure it may be different in your neck of the woods.

crashdive123
05-28-2012, 02:43 PM
That's a cool tip. Thanks.

Rick
05-28-2012, 03:54 PM
That is a neat tool. Thanks.

hunter63
05-28-2012, 07:50 PM
For those that have wood fence post set into concrete already you might try this, I made a T-handle screw by welding a 1 1/4" round bar about 16" long onto a 1" x 12" long screw , drill a 1/2" hole into the broken post and screw in your T-screw, it should come out fairly easy, I've replaced a dozen or more using this method, you may have to taper the post a bit to get it into the concrete but it beats digging out the concrete, now all new fence post I've used black pipe about 1 1/2" OD set in concrete I have a section of fence 20+ years old using black pipe thats as straight now as the day I built it, now this is the Mojave Desert and the water table under my property is 100FT so I'm sure it may be different in your neck of the woods.

a T-handle is a great idea, wish I would have thought of that or knew about it when we accross the fense neighbor and I replaced 3 broke off 4x4 posts.

We did leave the concrete in the ground, and drilled hioles in the wood, split it and pulled it out a bit at a time......PITA.

You are correct a little off the hew post and they when right back in the holes...still standing after about 7 years.

finallyME
05-28-2012, 09:09 PM
As an update to this post (get it, post). After reading your responses, I called my dad. He gave me the same advice, just pack em in, no concrete. He did a fence in the same general area (about 30 miles from here) and it lasted a pretty long time. Anyways, then I went and bought 40 pressure treated 4X4's. I then went and asked a neighbor (who used to have a fencing business in the area) and he said that there are so many rocks in the ground, an auger would be pointless. Just use a digging bar. So far I have been able to dig out one old post in concrete, and set one new one in its place. Some of my fence line I am increasing the number of poles from what was previous. I shouldn't need to dig out the old concrete, just dig a new fresh hole next to it. But, there are sections that I will have to dig out the old ones. I am thinking about paying some of my scouts to dig 'em out for me. They need something to do all summer anyways. At any rate, I plan to take all summer and maybe some fall to finish setting all the posts. That should keep the honey-do list away for a time. Then I need all winter to hang the fence on the posts. If I am lucky, I can drag this out for a year. ;) Wish me luck.

crashdive123
05-28-2012, 09:27 PM
That should keep the honey-do list away for a time. Then I need all winter to hang the fence on the posts. If I am lucky, I can drag this out for a year. ;) Wish me luck.

Trust me - the list is growing whether or not you know about it. You will eventually though.

Cast-Iron
05-29-2012, 02:14 PM
I just came across this thread. Without taking the time to read all of the posts, I'd like to offer you my two cents. (My apologies if I am repeating advice that has already been already offered.)

I realize money is always a factor, but that being said your time has value too. If I was planning to install a privacy fence I would belly up the difference for heavy gauge metal posts and feel confident that short of some natural disaster I would never have to deal with them again in my lifetime. Just replace rails and pickets every 10 to 20 years as needed. You will need to, if you haven't already, identify the type of preservative used in your pressure treated posts. Some preservatives react poorly with bare and galvanized metals and consequently they are highly corrosive. It's likely you will need to use stainless steel screws, bolts, and/or nails for any fasteners in contact with your treated lumber to avoid failure due to metal corrosion. The added cost of these fasteners might make the steel post in concrete a better option after all.

Good luck with your project!

finallyME
05-29-2012, 05:43 PM
I just came across this thread. Without taking the time to read all of the posts, I'd like to offer you my two cents. (My apologies if I am repeating advice that has already been already offered.)

I realize money is always a factor, but that being said your time has value too. If I was planning to install a privacy fence I would belly up the difference for heavy gauge metal posts and feel confident that short of some natural disaster I would never have to deal with them again in my lifetime. Just replace rails and pickets every 10 to 20 years as needed. You will need to, if you haven't already, identify the type of preservative used in your pressure treated posts. Some preservatives react poorly with bare and galvanized metals and consequently they are highly corrosive. It's likely you will need to use stainless steel screws, bolts, and/or nails for any fasteners in contact with your treated lumber to avoid failure due to metal corrosion. The added cost of these fasteners might make the steel post in concrete a better option after all.

Good luck with your project!

At first I wanted to put in the metal posts. But, in reality, my time has no value in this project. I don't get paid putting it up, and I am not using time up doing the fence that I would normally be doing something that pays me. The metal posts cost twice the pressure treated ones. Then, add concrete. I will be using screws, the added cost is worth it for me.

Thanks for the input. The more options, the better.

Beans
05-31-2012, 01:13 AM
I haven't dug postholes since the 50's. We always used "hedge or locust" for fence post. Some of those post had been put in at least 50 years before I was born and they were so damm hard you couldn't drive a stape in them. Never did see one of them Rot.