Fence Posts How and How Deep?

Question

Need to put some fence posts in which will stand 7 feet tall, how deep do i need to put these in the ground and what should i use and Met posts are rubbish and they will be 6x4" posts?

Answer 1

According to the American Fence Association, this depth is also determined by the local frost point. Which is the depth in the ground that water will not freeze in the winter. But traditionally 1/3 of the posts length should go in the ground and that is more than most people think. You said it is going to be seven feet tall and the other suggestions here say to put it about two feet in the ground. Well I doubt you are going to find any 9 foot posts and to cut a foot off of a 10 foot post would just be a waste of that lumber and would create less stability in the post. Buy 10 ft posts and put them in the ground three feet deep. If you are building a backyard privacy fence, I would suggest digging your post holes with a bell shape and setting them in premixed concrete and possibly an agent like quick-rok™, which will cause the concrete to set faster and be of a much higher psi. By using a "bell" shape, this will make the bottom of the post wider than the top and it will be impossible for the post and concrete to pull up out of the ground without pulling the ground up itself. If you can dig this bell shape but also try to make it have four sides like a square, it will be even more stable. You can take it one step further by shooting some nails into the bottom of the posts, with the ends sticking out, which will help keep the post from moving within the concrete itself. If you are using cedar posts, don't use concrete because they will react. You would want to dip the post bottom in an asphalt paint before concreting it, our just tamp it and not concrete it at all. I am going to stop now b/c I could go all day about how deep the posts need to be set and how to do it but I hope this helps! I also left some links that will be of some good help!

http://www.productionfenceworks.com

http://www.beautifulfences.blogspot.com

Answer 2

All good conventional wisdom.

However , I'm in N.East & frost heave is an issue.

Have set & removed a few posts over the years.

Have to consider soil conditions as well as frost concerns.

If the soil holds moisture I gets soft in rain, posts can still lean if there is wind pressure on the fence..

I set the posts "dry" by digging the post hole ( about 3 feet in my area).

With 7' above ground that would mean 10 foot posts.

Add a shovel full of 1" or 1-12' crushed stone to the bottom drop in the post level & ram crushed stone around the post.

It allows water to drain away from the post which helps w/ rot & as mentioned a preservative is a good idea.

No concrete to mix & you will have an easier time if you need to remove & replace posts.

If you need to remove or replace posts , just pull them out .

THe stone just falls back into the hole.

If posts do shift, lean on them & ram the stone around it again.

Can't do that w/ a gob of concrete at the bottom.

You still have to dig , but not messing w/ concrete is nice.

Best regards

Answer 3

10 Ft Fence Post

Answer 4

As a general guide, 20% of the post should be underground.



You will need to increase this if there are fencing panels, or an exposed site, or soft ground. Safely reduce if the posts are holding training wires, or the ground is firm or the site is sheltered from the wind.



The range would therefore be 15 - 25% of total length underground.



This gives, for 7 ft above ground, a range of 15 - 27 inches underground.



Wrap in polythene and use dry concrete both worthwhile suggestions.

Answer 5

if the posts are only 5 ft. then you only have a ft. to play with.i like to install fence posts at least 2 ft. you can probably go a few inches more and it will be fine that the pickets are higher than the posts.your not looking for the top of they pickets to be level with the top of the posts anyways.look to see if you can get away with the top of the fence to be about 6 inches above the posts,that will give you a foot and a half in the ground.if possible you may want to retun the posts and get some new ones that are at least 6 ft.if it a 4x4 post thet you are using it may be cheaper to buy 12 footers and then cut them in half.good luck and if you have any further ??? email me

Answer 6

As a farmer for 30 yrs or so 36 inches to about 42 is the normal for setting corner post that hold tension from 1000 ft of cable your local code may have different #'s but we use 36 - 42 deep. we also use roofing tar to seal post from water before we drop in hole.

Answer 7

In the event that you need to discover pleasant thoughts for woodworking i can propose you to check a website ( ( woodworkingplans.kyma.info ) ) It's perfect in the event that you are simply starting out or in case you're a prepared carpenter. It has thousands and thousands of woodworking arrangements and you have a CAD/DWG software to view and alter the arrangements. You have regulated instructions with photographs and excellent blueprints and schematics. On the off chance that you are a beginner this is the simplest approach to start your woodworking projects, and on the off chance that you already have experience you can at any rate discover a ton of interesting thoughts!

Answer 8

They need to be in the ground about 2 feet minimum id say, dig a 2-3 foot deep hole, 2 foot square'ish fill the bottom with rubble , then concrete the posts in. Square them up with a spirit level and then nail some supports to the posts while the concrete is setting

Answer 9

Wooden fence posts?

At least two feet, and wrap them in a strong polythene before pouring in the concrete

Answer 10

Here in Michigan the post need to be 42" deep.That is our frost line.You may want to check your local building code for your height of the post.Code is for no more then 72" from the ground.

Answer 11

im a builder in uk . i would dig the hole 30"deep for a 7 ft high fence ..as for answer no 1 ..you don't need a hole that wide ..and i never use rubble ..just a wheelbarrow of semi dry concrete ..then ram earth back keeping an eye on spirit level ..been doing it for 40 years ..never had one blow over yet

Answer 12

Hey there,

To get thousands of woodworking projects,

you should absolutly check this http://www.goobypls.com/r/rd.asp?gid=294

Bye

Answer 13

Superson has got it right , plus paint the bottom 3 feet with creosote or bitumen .

Answer 14

Usually 2', at least in areas that freeze. Check w/ your local Building Dept.

Answer 15

Rule of thumb is one third in the ground and two thirds out of the ground.

Answer 16

I would say 450mm (18ins) deep and every 1.2m (4feet) apart

Answer 17

as long as the bottom of your hole is below frost , it doesnt matter how much of the post is in the concrete...buy 8 ft. posts and put a foot of it in the concrete...

Answer 18

A rough guess: 15 feet.