What is the procedure to attach a bolt down post support to a fast set concrete base post? WHat type of bolts and what size should I use to attach this? One of the posts will support a 39" wide gate, the other two will support a 8.5' wide horizontal fence http://www.quikrete.com/ProductLines/QuikTubeBuildingForm.asp -this is the tube enter image description here

http://www.homedepot.ca/product/bolt-down-in-khaki-4-in-x-4-in/971849 -this is the post support

The final result should be something like below but at ground level. BTW, the one home auger seem to have bits shorter that 3' which is how deep I need to dig here in Toronto to put a post in the ground. I am not sure if this is valid for this type of post enter image description here

Here is the picture I am referring to in my answer

enter image description here

  • Be aware that these post supports don't do well against resisting the leverage of a gate trying to topple the gate post and will be prone to gate sagging unless you have a way of tying each gate post to its adjacent fence post with tension elements or use a gateway span beam tied to the tops of the gate posts to keep them plumb. Commented Aug 23, 2015 at 3:21
  • I also feel that the bolt bracket is not strong enough for a fence post, given that the pivot weight is at that bracket position. i.e you will get lots of sagging. Can you not support the top of the post with a section of adjacent fence? or is it free-standing?
    – Hightower
    Commented Aug 26, 2015 at 11:02
  • It is not free standing ...the garage is at one end, the neighbor's fence at the other. The brackets will hold. The forces are not that big. You have to check your support to see if it is made to support fences, some of them are (the above one is but the other one that I mentioned in my answer was ..so and so)
    – MiniMe
    Commented Aug 26, 2015 at 11:10

2 Answers 2


If you haven't poured concrete yet, use "anchor bolts". (Ref: Simpson Strong-Tie Model # SSTB16-R, for a visual, though it's probably too long and wrong diameter.) I'd use ones around 12-16" long and as big a diameter as will fit. Get galvanized. Bolt them into the base (nut on top and bottom) and use that to maintain alignment while the concrete sets. Once the concrete has set, remove all the nuts, set the base, shim as necessary with metal washers, and bolt it down. For bonus points, add concrete below the base after shimming but before final bolt down.

I can't remember if you have a section of fence adjacent to the gate, but do your best to tie everything together as much as possible. Gates are hard on posts.


The answer to the above (I learned this after trying to actually do it) was this: you can not do it.

this is not going to work, not in a decent or acceptable way There is two type of bolt down post supports like the one I posted in my initial message. The one that you are looking at in my initial message needs the concrete foot to be around 10" diameter which is huge, it is an overkill. You can find a smaller one which will almost fit in a 6" diameter concrete foot. The problem with this last one is that it needs 2 screws on each side (8 for each support) and if you need to align your posts and the post supports everything becomes a nightmare because you have too many things to align for 3 posts in my case

Since my fence segment will attach to the garage at one end and to another post that belongs to the fence that separates us from our neighbor I guess these two ends will add strength to the fence. These being said I decided to go with this: http://www.rona.ca/en/heavy-duty-spike We already put these in the ground and installed the posts on top of them and they look solid The only concern that I have is what will happen when the soil freezes. These posts are three foot long but they are set in a paved area so not much water will get under The fence was designed to be removable and if these have any problems I will remove them and I will pour concrete footing and I will stick them in concrete :-)

As far as the method to put the bolts into the foot, use this method: cut a thin square piece of plywood, large enough to cover the section of the tube used to form the concrete foot. Put your bolts through it and align their head at the head level. After you pour your concrete, while it is still soft stick the heads of your bolts into it (see the picture above) and rest the plywood on the tube . Make sure everything is aligned as you want. This is how you put multiple bolts into a concrete foot and you maintain everything perfectly aligned. At the end you remove the plywood (cut it, it is not reusable) . Edit: you can make the wholes slightly larger than the bolt and use nuts to adjust the depth of the bolt that will be in concrete. Then you can reuse the plywood. This will introduce some alignment errors. Use a template if you use multiple boards, you will need perfect alginment

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