Decks, Patios, Porches and Docks - Fence construction

I hope you can help me with this. I'm getting ready to fence in my back yard and am searching for anchors for the fence posts.

I want to build part of the fence on top of an existing rock wall, using 4X4 posts 4 feet high. Would these anchors serve to hold these short fence posts? (The description says they are not suitable for fence posts. If not, is there something that would be?):



4 X 4 Galvanized Post Anchor [Contractor Pack of 10] by USP Lumber Connectors
SKU: 6955686x10
Post Anchors 4-Sided - High-Capacity 18 Gauge Post Size Inches = 4 X 4

Retail Value: $55.50
DoItYourself.com Price: $46.82
You Save: $8.68 (16 %)

The other sections of the fence will use the normal in-ground post holes. I would like to use "wet" anchors set into concrete, instead of setting 4X4 posts themselves in the concrete. Is the following product suitable?



4 X 4 Wet Post Anchor [Contractor Pack of 12] by USP Lumber Connectors
SKU: 8817017x12
Wet Post Anchors Galvanized Steel 12 Gauge - 3-1/2` X 3-1/2` X 8-13/16` Post Size = 4 X 4

Retail Value: $56.82
DoItYourself.com Price: $51.65
You Save: $5.17 (9 %)


I would very much appreciate your help and advice.



Jim Gansle

P.S. I hope this is the right forum to post the question in. If not, I'll repost it in the proper place.

USP tells you not to use those anchors for a fence because a fence has no top support. A 20 MPH will blow it over.

Anything that you put on top of the rock wall is going to act like a sail. It will catch wind and want to pull the rock wall over. Is the wall sturdy enough to accept this load?

The rock wall is ten to twelve inches wide and mortared and three to four feet high itself, so I think it will be plenty strong. The portion of the fence on the wall would be only four feet tall.

If this seems strong enough to you, I have the question of whether the particular anchors I referred to are the right ones. I've also seen ones that are basically three sides of a box with holes on each side to attach to the wall (bottom) and to the fence posts (side). Would these be more appropriate?

I've also read that another way to do it would be to notch the fence posts lengthwise for a foot or so, and rest the top of the notch on the top of the wall, fastening the remaining part of the post to the side of the wall. Visually, I would rather have the fence on top of the wall. Besides, doing it this way would probably entail shimming or cutting the inside notched parts of the post to get it fastened straight up and down. The rocks are not very rough, but not smoothed either.

Thanks for your interest.

Check with your local building dept. Have no idea what the codes in Texas have to say, but I can tell you this. In CA, if the total fence is over 6 feet high, it HAS to be engineered. If it is 6' - 2" and NOT engineered, they CAN make you tear it down.