Electrical – fencing under electrical transmission line

I am in the process of building a picket fence (picket by picket). I made 8 inch holes and used 4"x4"x6' posts for my 4' fence. The upper back railing is a about 38" off the ground. So around 2 feet of the post is in the ground for every post. Corner posts are 8' posts and cemented into place. The tops were trimmed to the top railing to be flush. Also the 8' posts are buried deeper, tried for around 4'.

Cementing the posts into place can help and hinder in the long run. It will help keep it in place longer. But in northern climates the cement and post is likely to go through many freeze and thaw cycles over the winter. Once the treated posts dry out a little they will move away from the cement allowing water around the post to freeze. It will also take a VERY long time to dry out. This, even with treated posts, will cause them to rot faster. Not the mention the freeze and thaw cycles along with the extra moisture, are likely to cause the cement to not hold up.

For stability, I would do cement on only corner posts and gate posts. These will be stress points anyways. If you could get it compacted enough you might get away with doing crushed rock as well. The posts that are not set in cement currently in my yard are just as firm as the cemented ones, at least for this year. But also the ones not cemented in will be much easier in the long run to replace if needed.

A general rule (not sure if your neighbors abide to it) is to build the fence 1-2 feet inside your property line. You mention that the fence post is presumably in their property so even butting up to it would be in their yard. You best option is to ask them to join your new fence to it and get a simple contract to protect yourself. Either that or put up all four sides in your property.

You may also need to get a permit or permission from city/municipal/HOA depending on your location. Your neighbors could have even blocked you from getting a fence because of easement right between yards, all things to look up before this endeavor.

As for the height difference, it's more personal preference than anything else. Personally I'd recommend one size fence for the front of your preference and one size in the back of your preference which may or may not be the same. Like if you want front privacy but have nature in the back, it allows you to get away with 6ft in the front and only 4ft in the back. I'd mainly recommend the same size in both front sections if your yard is level otherwise it will look off from the street.

In the front you may want to fade the height difference but I wouldn't even bother in the back. Could be a nice design feature if it fades into a gate post or something.

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