how much cement for fence posts?

Reply

  #1  
Old 06-09-03, 10:12 AM
phil mcc
Visiting Guest
Posts: n/a
how much cement for fence posts?

I am putting in a 6 foot, wooden privacy fence and am using 4x4 posts and digging 8" diameter holes. The guy at the lumber yard where I got the material said I only need to use half an 80lb. bag for each hole. So, on one hole I put in about 4" of dry cement at the bottom, placed the post then mixed and put in the remainder of the 40lbs. It probably came up the post maybe 3 or 4 inches. This doesn't seem like enough cement to hold it. The directions on the cement bag says to fill the hole to the top which seems like overkill. How much is the right amount?
 
Sponsored Links
  #2  
Old 06-09-03, 11:26 AM
shofear
Visiting Guest
Posts: n/a
When I do 4x4 posts I use a hand post hole digger about 18 inches deep, and fill the hole completely with mixed concrete that I mix in a wheelbarrow, probably is about 3/4 bag of premix 80 lbs.
Guy
 
  #3  
Old 06-09-03, 01:04 PM
SillyMike
Visiting Guest
Posts: n/a
I think it also depends on frost lines, etc. When I did mine, I went down 40", dump about 3" of gravel, set my post on top, dumped about 2 80lb bags (mixed in wheelbarrow) and made sure my post stayed level. (I tamped the soil prior to gravel).

My way is probably WAAAAY over-built. But I can tell you, there isn't a more solid fence in the neighborhood, and my heavy 6' shadowbox fence doesn't move and inch in either direction.

I know before I did it myself, I was calling around out of 5 places I called 4 said they wouldn't do it with cement -- and if they would, the price is double.

HTH,

Mike
 
  #4  
Old 06-09-03, 03:11 PM
Member
Join Date: Mar 2000
Location: Arlington, WA
Posts: 9,238
Received 0 Votes on 0 Posts
And I don't use wood posts. Got tired of replacing them every 10 years or so. All of my fence posts are now made with 12X12X6 slump blocks. 8" round footing about 2' deep and 4" below grade, and the 4" above that is an 18" or 24" square. 2 or 3 sticks of rebar set in the footing that go almost to what the finished post height will be, and once the mortar of the blocks has dried for a few days, fill the tube with concrete. Initially more expensive and more time consuming, but you only do them ONCE!!
 
  #5  
Old 06-09-03, 03:35 PM
SillyMike
Visiting Guest
Posts: n/a
Talking

Wow! And I thought my method was going overboard!
 
  #6  
Old 06-09-03, 04:00 PM
Member
Join Date: Mar 2000
Location: Arlington, WA
Posts: 9,238
Received 0 Votes on 0 Posts
Actually, I don't see them as being that overboard. This is the post that is now required for every perimeter fence (but not the property line fences) in all of the developments in the City of Redding. Their other option is a block wall. Reason is simple -- these posts will be here when my grandkids are old -- and the youngest one is still in diapers!!

My back fence has been up for 15 years so far, and has withstood several 80 mph wind storms in the middle of VERY wet winters. Some neighbors for 1/2 mile in either direction have replaced their fences a COUPLE of times in that time span. In about 6 or 8 years, I MAY have to replace the wood fence panels between my posts.
 
  #7  
Old 06-09-03, 06:01 PM
NutAndBoltKing
Visiting Guest
Posts: n/a
I think the old expression goes something like this; "There's the right way, the wrong way, and the Army way."

I mention this saying only because I have bid DOD & Army jobs for fence (and other work) and their specifications for that type of fence requires a hole 3X wider than the post and 8 sometimes 10 inches below frost. A 4x4 post would therefore require a 12" wide hole.

The DOD & Army specs that I have reviewed and bid with seldom if ever required that each post be set in concrete. If, for example a run had 10 posts, only 4 or 5 had to be set in concrete, the remainder would just be set in crushed stone or gravel - unless it was in a very windy area like an airport. When concrete was specified the entire hole had to be filled.
 
  #8  
Old 06-09-03, 10:28 PM
Member
Join Date: Mar 2000
Location: Arlington, WA
Posts: 9,238
Received 0 Votes on 0 Posts
So, NutAndBoltKing, if I'm following you correctly, a 12X12X6 slump block post would require a footing 3' in diameter?? Hmmm... My frost line is only about an inch, maybe 2" at the most, so this footing only needs to be about a foot deep. Leave it to the Army!!!
 
  #9  
Old 06-10-03, 06:26 AM
NutAndBoltKing
Visiting Guest
Posts: n/a
Smile

Hehehehe lefty! Here's the good and bad 'bout those Army jobs: The good - lucky for me (back when I was - no kidding, the "FenceKing" LOL) all the posts were just 4X4s and only had to be sunk 3 foot or so plus 1 for the frost. Nice and easy and no inspectors for miles. But the bad - digging on Army bases can be an adventure .... no, it's wasn't the rocks, it was finding all those old live shells they buried and forgot about.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: