Fixing a fence. Need advice.

[Outsider]

The fence in my nack yard has seen better days. It's leaning quite a bit (25-30 degrees in some spots) and I'm gonna straighten it sometime soon.

Currently, the fence posts (4x4 which are only the height of the fence) are only supported by a metal spike that is in the ground, and to which the post is bolted to. The fence itself is probably 4-5ft high, so it's pretty short.

I only need to do 4-5 posts, as the rest of the fence is fine.

Questions:
From what I've read/seen, the way fence posts should be cemented in the ground. Is this the preferred method?

I read somewhere that the frost line in Toronto is 1.5m (almost 5ft). Is that how deep I need the concrete to go? That seems kinda excessive.

Concerns:
I'm a little worried that if I take the fence apart, cement some posts, and then try to re-assemble the fence sections, things will not line up. I'm worried the fence sections won't fit back in (either too loose or not enough space). Any thoughts on ensuring this goes over well?

I read somewhere of a method to fix leaning fence posts where a secondary post is cemented and bolted to the main post. This would take away from the aesthetics of the fence, but would ensure that the fence sections keep their spacing (since I would likely bolt the cemented piece of lumber to the main fence post before pouting the concrete).

Any thoughts/suggestions?

[Outsider]

Nobody has any advice?

[Dr Butcher]

If you pour cement, make sure the bottom of the hole is wider then the top, or, shaped like a pyramid. This way the frost will pull down on the posts instead of heaving them out of the ground the way it does if the hole is dug narrower at the bottom than the top.

This explains it better than me:

http://www.gatewayalpacas.com/alpaca-farming/fence-building/setting-fence-posts.htm

[Pete_Coach]

My advice is to replace the entire fence segment. Your concerns are correct. If you disassemble, you may not get it back together properly.
As for the frost line, yes you need to get below but I always thought it was only 1 meter deep in most places in southern Ontario.
You also do not need to put each post into concrete, every second one should be OK.

[hyperactiveme]

every post needs to be set properly! You can use traffic bond if you don't wanna use cement. I agree, you should replace fence segment if you are not sure about you ability to match up.

Good luck.

[Pete_Coach]

every post needs to be set properly! You can use traffic bond if you don't wanna use cement. I agree, you should replace fence segment if you are not sure about you ability to match up.

Good luck.
While it is correct that they need to be set properly, I disagree with them needing be set in concrete. You do not need a concrete anchor ever 8 feet, every 16 feet is sufficient and is standard practice.

[sunjwd]

(Thanks for the reply via PM with more detail.)

Since the fence posts are currently held up by those green
post spikes (possibly from Home Depot), maybe a simpler
repair can be attempted?

For example:
If the in-the-ground spike parts are fine (ie not pulled out of the ground) but the above-ground bracket parts holding the posts are mangled,
then they can be pulled out and new spikes put in. They are around $8
at HD. Going this route, you can even replace the spikes with higher
quality spikes.
(I am a fan of the OZ-post, but they cost more at ~$20 each and I only
found them at specific Home Hardware in Aurora.)

If the spikes are partially pulled out of the ground, then I guess they were not adequate to hold the posts and it may be better to put cement anchors (with post holders) in their place.

For a DIYer, digging post holes is a pain: renting the auger, moving the
concrete and mixing it, and worst of all getting rid of the dirt afterwards.

[redflagdog]

do not put a wooden post in concrete. It will rot quickly.

[l69norm]

....If the in-the-ground spike parts are fine (ie not pulled out of the ground) but the above-ground bracket parts holding the posts are mangled,then they can be pulled out and new spikes put in. They are around $8at HD. Going this route, you can even replace the spikes with higher quality spikes......

+1, seems a lot simpler than trying to set new posts in the ground, especially if the rest of the fence (using spikes) is fine. There's some spikes that are adjustable, so you don't have to get the spike exactly level.

[FenceMaster]

Frost line ranges from 3 1/2' to 4', don't need to dig deeper.

[Drthorne]

I wouldn't bother with concrete, just dig a 4foot hole and pack gravel around the post.

[tallAJ]

i would definetely go with concrete but that all depends on soil type and drainage, you can wrap it in poly if you are unsure about rotting.

[hyperactiveme]

wow! Do some research before taking your advice from this particular thread. That's my advice but to each their own.

[pshch]

I wouldn't bother with concrete, just dig a 4foot hole and pack gravel around the post.

+1. you will thanks yourself if you ever have to fix it again. removing concrete base is not fun at all.

The rule of thumb is 1' below ground for every 2' above, so for 6' fence you need only 3' deep hole.