Fence posts

I am going to use 8 ft treated 4x4 posts for a wooden stockade fence.I made the holes 32 in deep and only as round as the post hole digger made them.Is that good enough,and I will fill with concreate?It is a short run of only 60ft.

Fill with the dirt you removed not concrete or thew posts will rot off very fast. Cement/concrete tend to hold water so posts rot off extra fast. Had a guy build corner posts with 6X6 posts that where treated and in less then 5 years all the post had rotted where they went in the concrete.

I agree with old no concrete fill. Just put the dirt back in and tamp it in with the round end of a spud bar.
Now as for the depth ? how far north are you ? You need to be below average frost depth. Always heard 36" was about right for north central Ohio weather. So if no farther north than this you should be fine.

New Jersey

32" to 36" ? may be just fine. It works for here. By looking at the map you are about as far up as me.

Hi John;

Maybe this is obvious, but don't put all dirt back in before you tamp it down. Tamp it about every six or eight inches. I like to use something heavy and flat on the end to pack the dirt down really hard.

Stan

The one thing that stands out with 6'x8' typical stockade fence panels, is how do you fasten to the top rail by going to that depth with an 8' post? Maybe your panels are less than 6' tall ? You really need a 9' or 10' post for a 6'x8' panel and have the post deep enough.I always used 10's for these jobs, then trimmed the tops down as needed, and getting more of the post into the ground.

Its a wise choice to go with ground contact pressure treated lumber, CCA treated if you can get it and or order it.

The problem created with concrete embedded posts is like Rich said, the joint at the post and the top of concrete, not being sealed allows water in and below theres no weep hole, so the post will rot and lots of times its right at that location, just above or below the top of concrete. With a good mix and fussing with troweling it, you can get minimal shrink, and I would wonder if there is a non shrink material available for this purpose, I'd backfill with what came out of the hole. Gravel may draw water and pond around the post. Some backfill with dry concrete mix, tamped in place, using it as gravel.

.60 CCA posts in well drained soils could last quite some time, the .40 CCA lumber we used to sell was rated for 40 years on the labels as I recall.

Yup. Dug and filled many a post and rail hole. After you dig the hole and set in the post you put in about 6/8 inches of soil. Tamp it with the head of a "shale" bar really good. Add more soil like another 6 inches and repeat. When you are finished you will not have any soil left to fill about 5 inches of the hole! This is how you know you did a good job. Fill in the top of the hole with some extra soil. You should NOT be able to wiggle the post at all. A loose post will just not ever tighten up.

The top rail is at 64 in high 64 high + 32 in ground=96 (8ft)

Must be a different panel height, or rail spacing, 32" is decent, but 24" is marginal with wind load. I have one fence that I argued about this with and the results back up my point, hard to win with family etc, stubborn father etc. 6 years in, 3 panels down, problems with shallow posts, + they used concrete. One I did in '07, stands to this day without one problem and I see it regularly, as its a friends place. One shot while panels were going up.

I back fill with pea gravel. If back filled with dirt or cement here in TX in the dry summer the dirt will shrink, crack away from the post or cement leaving it loose. The loose pea gravel will settle, filling the space, keeping the post tight.

Power company here is now back-filling poles with expanding foam, and only enough dirt at the top for grass to grow in.

For a 6 foot fence I always wanted my top rail at about 5 feet which left 3 feet to go in the ground for an 8 foot post. With a 10 foot post I would throw away 2 feet of every one. I have never used the pre-built panels though.

I have 3 in 1/4 galvanized lag bolts with flat washers,good enough?

John, the only thing I will add is to make the holes a little larger than the posthole digger. That will give you enough room to tamp it in good. You'll know what I mean if the hole is too small.

I tend to go deep with posts, ones in the photo are hand dug at almost 4'. Smaller runs, not too bad with cut offs, but 8's really can be tough to work with and minus the reveal from the top of panel to top of rail, you are just over 24" in the ground and that can be marginal, depending on the ground. I have a fence failing because of this right now, and of course they did not listen to me on these details, shorter posts are not my favorite with these types of fences.

Absolutely, size wise, I've never used washers but if not an aesthetic issue, no harm done, though uncoated or protected steel washers will leave rust stains, streaks as it weathers. Use care to avoid splitting the pickets, pilot hole the panels. I have used deck screws, (job in photo still intact today, it was done July of '07) compatible with the pressure treatment used on the lumber, which reminds me, galvanized fasteners,(galvanized coating) and ACQ preservative I believe are incompatible.

LUICD is so correct!
I was installing 8" X 8" timbers. (A SQRD + B SQRD = C SQRD)
I should have drilled the holes LARGER than 12" Diam.
Bob...

don't add concrete.the ruff edges of the hole will make ruff edges around the outside of your concrete.this will give frost a place to get hold of and heave your posts.just use well tamped dirt backfill.plus the bottoms of your posts should be below frost line.

The guys are right about tamping the bottom well. If the bottom is loose you will never get the post tight.

We use two to three inch gravel with the dirt from the hole and tamp every six to eight inches of fill. Works good until someone drives through the fence and it has to be dug out