Landscaper looking for post setting method.

Hello, I am brand new here but saw a lot of good info so thought I would join the community.

I am starting a small landscaping company and am wondering what would be a good post setting method for residential fences that will last. One option I am looking at is galvanized steel that could be reused after the fence has rotted away. I really would like to know a good wood post setting method I can offer my customers that is cost effective and will last as long as possible. Wondering if anyone can comment on wood types and treatments, post depth, backfill, concrete vs pounded vs backfilled after augering and setting by hand, treating the ends, flaming etc. Everything. One repeatable method that is better than let's say pressure treated post with gravel, encased in concrete, you know, the usual. Is there something I can offer as a demonstrably better method than what people would typically install?

I have some knowledge of wood and have researched lightly into charring. Wondering what Jay c white cloud would have to say as I've read a lot of his posts on a few threads and he seems super knowledgeable.

Thanks a lot guys.

What rot resistant woods do you have at your disposal in your part of the world?  I hear black locust is very rot resistant.  In my area, the best we have is cedar.  I had some cedar posts that were pretty much shot after 16 years but I don't know what condition they were in when they were installed.

My local big box hardware store has 4" EMT conduit but it's pricey.  Maybe in a bulk order it would be affordable.  I'd think that could make for a decent post.  I've used 1" EMT to hold up deer fencing between beefier corner posts and it did the trick and looked shiny after 5 years.

Hi Shawn, welcome to Permies!

I just replaced some stockade fencing recently. I noticed that the posts were rotten in the top foot of the buried section.
What's the reason? moisture? air? soil microbes? Deeper down is sand, and not much happened to the post down there.
One of the worst posts had been backfilled with 3/8 gravel, and it was rotten almost to the bottom. (and the hole was a pain to dig out with post digger, as the gravel kept falling into the hole... so I had to dig as big a hole as the last guy did! a 15 gallon hole...)
Did the gravel allow for moisture to flow down and around the post? Did the other posts set in soil let the surface water run away instead?

I feel as if any suggestions (like gravel under the post, and concrete around it) are to justify purchasing *their* product (concrete and gravel) or whatever...
The added weight of concrete and the "form-fitting" filling of the hole it offers are some benefits, especially for gate posts. I've seen failures of posts rotting through with this method too.

Yes, a "forever" fence post solution would be great, but also could be a pain to "undo" in the case of repairs due to accidental damage. (what does this mean to you if it's you doing that job?)
It also means you need a "forever" fence panel to go along with it, does that exist?

Commercial construction often uses the most durable, long lasting stuff available. Usually in the form of "the next bigger size" like 6 inch posts instead of 5 inch posts, 2x4 rails instead of 2x3 rails; and also high quality materials, best grades of lumber, best quality galvanizing, etc.
My guess is that if there were "a substantially better option", commercial installations would be using it.

And don't forget...Sometimes the time for replacement is a welcome opportunity for change.
A different fence, different line, no fence anymore...

I would have to say that Black locust would be my choice. Placed hand dug directly in the ground, dirt tamped.
Costs would be high having proper posts shipped. When you consider it is  a hundred year plus post, the cost is not that bad.
Cedar has a reputation as long lasting,rot resistant fence post. It is better than other common wood.
Unfortunately only old growth cedar heart wood is truly long lasting.
 

Where are you? Your climate and soil conditions matter a great deal, maybe more than the post material.

Osage orange are the gold standard where I'm from.  When I was a kid I helped my grandpa fix fence that was put in by his grandpa.  The barbed wire had rusted away (twice) but the posts were still there.  

I have also used fresh cut osage posts in swampy areas and had them root and regrow like cuttings.  

Shawn Harris wrote:encased in concrete

Wood posts set in concrete rot faster because the wood will shrink a little bit, which opens up a tiny little gap that will always hold water due to capillary action. A pressure treated wood post tamped in the soil around here lasts 20-30 years; one set in concrete rots off in 5 to 10.

As far as getting them in ground goes, if the soil is dry and gravelly, a shop-vac will suck the soil and rocks out of a fence post hole quick and easy on your back.

I'm in southern Ontario, Cobourg area, hour east of gta.

Concur that concrete is just about the worst method - it feels good and solid at first, checks all the boxes "for doing something" and is a liability thereafter.

For wood posts, I prefer to just set them in gravel.  I tend to go much deeper than normally recommended - without the weight and surface area of a blob of concrete the deeper hole provides more friction against uplift and a greater arm against leaning.  I tamp the gravel carefully.  While putting any wood post in the ground creates conditions for rotting, the gravel mitigates water problems, requires less equipment to install and if the post is ever removed/replaced gravel is much easier to deal with.

In Wisconsin a local fence company made a name for themselves by using steel posts just pounded in.  The posts had two wings that flared out underground and provided greater stability.  These didn't rot and weren't subject to frost heaving, but I never liked the bare steel post, and the machine to pound them in made it a non DIY job.

My Wisconsin solution was to use split steel posts - one piece into the ground and then a steel post mounted to that.  I used ones from Oz Post (https://ozcobp.com).  I'd tried using the spikes with standard 4x4 timbers but found that it was nearly impossible to drive the spikes in a co-planar line.  Every rock or root would make it twist. Instead I used 2 1/2 round steel posts because then I just had to get them aligned in two planes.  With an electric jack hammer the spikes go in fast... its clean but noisy.  I then built wood boxes to cover the steel post.

Others make similar spikes - OzCo seems to have the heaviest ones with the largest range.  They can be pulled and re-used too.

I’ve had a thought about my own tired picket fence. Could one pour solid concrete footers and mount hardware to the top of those to hold a post? Probably not practical for a long fence, but for a shorter length.... what do people think?

D

Daniel: Absolutely can be done.  There are multiple types of brackets, some are set in wet concrete others are attached to dry concrete,  and then the fence post is held up above the wet soil.  Not a bad solution if you just have access to commercial pressure treated posts, enjoy mixing concrete and like digging big holes.

I prefer the spikes ... both get the wood out of the ground.  But a lump of concrete is just about forever and you have to worry about frost heaving too.  Spikes are reusable and, if necessary, recyclable.  Also made in China ... so there's that.

Daniel Ackerman wrote:I’ve had a thought about my own tired picket fence. Could one pour solid concrete footers and mount hardware to the top of those to hold a post? Probably not practical for a long fence, but for a shorter length.... what do people think?

D

Sure can. I did this for my mailbox last year. I poured concrete into the hole in the ground, then set J-bolts into the wet concrete. I scavenged a cedar post from an old cattle handling facility on site to use as my mailbox post, thinking that with an air gap between it and the concrete, things will stay dry and my post will not need to be replaced while I am alive due to decay, but in the event a drunk guy knocks it down I hope to just fashion new brackets on a new post to fit the J-bolts.

I do think the post method has to match the climate...that said, anything that keeps the wood out of contact with moisture, soil or gravel is ideal.

Pencil posts (round, debarked, pointed end) or galvanized poles pounded in are the best option, if going straight into ground without spike or concrete.

I am in the process of installing over a hundred galvanized, 8 foot poles, precisely because the wood in concrete posts have rotted at ground level (I'm in BC, on Vancouver Island - aka, the "wet coast").  

Mark, hold pole, husband beats with tractor bucket, I level and adjust, hubby pounds with tractor bucket...until deep enough.

I HAD intended to place these posts in dug holes with concrete, even have a skid in the shop bought for this project. The thing is, at the end of the day, the undisturbed earth is a much stronger placement, and way less hassle then digging, forming, pouring and placing the pole.

We are running the metal roof panels left to right, not up and down; although everyone told me I couldn't and it would not work. I wanted an all metal fence, using wood stringers top, middle and bottom made absolutely no sense to me; plus the ridges in the roof panels, running left to right, supplies all the rigidity required.

Lorinne Anderson wrote:The thing is, at the end of the day, the undisturbed earth is a much stronger placement, and way less hassle then digging, forming, pouring and placing the pole.

I second that.  Ranch-scale fencing can be done with tractor or skid-steer mounted post drivers.  Some are weighted hammers, newer ones are hydraulic impact drivers.  They can take a blunt railroad tie and just ... push it into the ground.  Everything I've seen agrees that this is more resistant to pull-out and tipping than just about any other method.  But it can still rot...

Two questions ...  
1) What size tractor?  My 21hp could maybe convince a t-post to go in, but that's it.  Larger excavator and dozers certainly have weight to throw around, but not mine!
2) the steel roofing.. were the  naysayers just worried about the lack of support between the posts?  I'm just imagining that a wind-storm could exert tremendous pressure on the screws and possibly pop them off, or would leave the fence with a scallop bend in it.  Please do report how it holds up!

The pictured section has been up a year, and is broadside to the wind. I put the posts every 5-6 feet, used fender washers beneath the roofing screws, into predrilled pilot holes.

As to tractor size, Um, not tiny but not very big either - no post driver (much better idea) just banging the bucket on pole repeatedly while I adjust for plum.

I've heard that if you load the bucket with some weight it pounds with more oomph.

Mike Haasl wrote:I've heard that if you load the bucket with some weight it pounds with more oomph.

That's what I tell my wife but she still says I need to go on a diet...

That steel fence looks pretty good, to me. Hope it stays that way for the years.

The bottom on the soil gives me pause, though. I get paranoid about soil touching structures, especially if it can be avoided more or less easily.

I have been known to clear 12" below the fence line, remove sod, level, lay a layer of standard asphalt shingles (discourage plants sprouting, with extreme prejudice), 2" of leveling sand and then 12" tiles. I guess I was having a neatnick day, but I had just finished repairing 50' or wood fence where the bottom was set in soil and rotted out.  I got a little bit of attitude about it. If the new fence had been more than 50' I probably would have had to figure out something more practical. That was 15 years ago and it still look neat.

The last few years I have have set a few 4x4 cedar posts into concrete sand, which is supposed to drain exceedingly well. These are light duty applications, the most stressed being a paneled gate weighing maybe 35#. Sand gets tamped as well as possible. On one I laid long stones against the post at ground level, oriented across, perpendicular, to the prevailing stresses. Theory is that the most moveable part of the post is right a ground level and this 12" long rock gives that post that much cross section to push against, instead of the 4" of wood. That's been doing the job for a couple years and hopefully I'll never find out how long it ends up lasting.

My understanding is that posts live better with good drainage, more good drainage and then wouldn't mind even better good drainage... Hence the concrete sand, as above. Gravel would probably be more solid and and move less easily, though; but  my reading said that concrete sand resists incursion of soil quite well whereas gravel gets filled up (from the sides) w/in 5 years or so, thus greatly reducing it's initial excellent drainage.

Another thing I have done with wood posts is to place  2x4x8 bricks vertically against all for sides of the post - sunk in the ground about 3". The lawn grooming folks _love_ their string trimmers and I just didn't like the idea of their "cleaning up" the bottom of my posts! Another reason to keep 12" clear beneath the fence line.


Cheers,
Rufus

I ran a fencing business in Australia for 10 years.
I believe the best solution is having the post embedded in the ground, rather than attached to a block.
IT gains a lot of strength form the depth of insertion, I always went 600mm down.
Timber will rot near the surface and its a function of the wet / dry cycle. You see it on piers , lamp poles.
I found adding about 10% portland cement to the dry soil volume from the original hole, rammed back in at short levels [3 inch]
and either watered a bit or use the soil moisture do its thing worked well.

In sandy soil they were almost as strong as concreted posts.

Lightweight concrete posts were available to me, and set into the soil / cement mix they lasted a very long time.
When I went to renew the timbers attached to them after 25 years, the posts were all good.

Heavy galvanised thick walled steel posts in concrete work well, the soil / cement mix was ok, but people expected the steel posts to with stand much greater loads of rubbish etc against them.
Light section electroplated galvanised steel posts are no better than cheap wood.