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One of the projects for 2015 that I need to get too is to rebuild the fencing around my redoubt property.  The current fencing has already started to rot and break off, and it appears to be less than 10 years old.  The issue is I know very little about large scale ranch or homesteading fencing myself.  When I have a question I normally go straight to the best resource on the web, survivalblog.com. I searched for fence, and many other versions. I found a very good article called “observations from fence building.” However the article is primarily lessons learned on actually building a fence. Things like “drink a lot of water.” I was looking for “what type of fence to build.” I really could not find a “receipt” for a decent fence. Thus I started to look around the homesteading-blog-o-sphere a few other web sites but basically thought to write up this article and ask for feedback.  I purchased a book, which was not very useful once again it was more about how to build a fence, not which fence to build in various situations.  Let’s apply the skill set of my over fluffed title of a so-called Systems engineer to designing a fence for our homestead.

Fence Break force

Fence Break force – A six-wire fence applies 1,200 to 1,500 pounds of pull to a corner post

First the Marketing Statement or “what the customer thinks he wants.” We need to build a perimeter fence around 5 acres of land, primarily flat with a few grades. This land will be a “defensible” homestead. The purpose of the fence is to keep our (eventual) animals (including the children my wife is so in love with) in and to keep predators out.  All kidding aside the inland Rocky Mountain west or American Redoubt is not suburbia.  There are very real wolf packs (that liberals love to have other people’s families live near), bears, and very real coyotes just to name a few predators with the ability and aggressiveness to snatch a 5 year old child off your property.  You didn’t think taking your wife to the range to train her with the .223 or .30 rifle was for fun was it?  This is “see a wolf, shoot a wolf” my children are more important.  I will feel better with a good fence around my homestead.   This is perimeter fencing project and we fully expect to have other additional internal fences around such things as barn fencing, chicken coop, orchard fencing, hog fencing the additional fencing around the home area. It would also be nice that if any choices we made about building the fence would assist in physically securing the property from entry by humans.

Then we reduce our marketing statement to a set of specific requirements. Because I feel like it, I will write this in actual good “requirement” writing style. This means we should not slide over to design, even though we always do.  The theory of requirements definition is if you catch all of the requirements you will end up with a product that performs the mission as design, no matter how complex.  Excuse the techno-babble. Just stay with me.

F01: The fence will be a perimeter fence.

F02: The fence will circle an area to prevent access.

F03: The fence will provide a physical barrier to small animals. Example sheep

F04: The fence will provide a physical barrier to large animals. Example cows.

F05: The fence will provide a physical barrier to small predators. Example fox.

F06: The fence will provide a physical barrier to large predators. Example wolf.

F07: The fence will follow the slope and undulation of the existing terrain. The terrain has moderate rolling (20 degrees) sections.

F08: All animals are assume to be under “hunger” (other choices include; weaning, breeding, boredom, fear) motivation to breech fence. I.e. this is not fencing to keep in a  bull cow.

F09: The fence will have a life in excess of 20 years when installed in the inland North West.

F10: The fence will provide a physical barrier to humans. (Objective)

F11: The fence will provide a physical barrier to automobiles. (Objective)

Although this appears to be somewhat over complicated, fencing has so many options.  To narrow the options you decided what you want to do with the fencing.  For example you could build this fencing for a lot less money if we were not concern with for example “small animals, or small predators.”  Now that we have used over complicated techno speak to say a fence will be a fence we move into design.  I think I can break the fence down into two or three parts; the posts and the actual fence itself. You could claim that the line post and corner or gate post are separate but for this we will not. I guess we can also include the “separate dissuade” wire. There seems to be a pretty standard approach to put a wire of either energized electrical wire or barbed wire along the top and sometimes the bottom of the fence. After reviewing the options we may go with barbed wire at the time.

GalvanizingProtection-Table6The actual fence itself. After reviewing the several various offerings it seems that some form of woven wire fence seems appropriate. It appears that welded wire can’t be stretched very easily and it appears not to conform to changes in elevations as easily, thus does not meet requirements F07 or the “follow the undulation ”of the existing terrain” requirement.  To accomplish both it appears we would need woven wire fencing or “field” fencing. To achieve the F09 or 25 year requirement it appears we will be looking at Class 3 galvanized woven wire fencing.   Wire is covered with zinc, commonly called galvanizing, to protect it from rusting. The length of time before fence wire begins to rust depends on the thickness of the galvanized coating.  In the paper Planning and Building Fences on the Farm it states to get the longer life we should use no heavier than 12 1/2 gauge galvanized woven wire.   I am unsure if the Rocky Northwest is considered “humid” (it is not like Florida, but it rains enough for dry farming), however if it is then we will be unable to meet F09 with any wire.  This paper Planning and Building Fences on the Farm was written for the University of Oregon by four professors;Michael J. Buschermohle, Professor, Agricultural Engineering, James B. Wills, Professor, Agricultural and Biosystems Engineering, W. Warren Gill, Professor, Animal Science and Clyde D. Lane, Professor, Animal Science.  I found it so useful I re-posted it here for future reference.

The best way to let smaller animals like sheep (and dogs) have more areas but to try and keep them we seem to need 4” x 4” spacing. This is sometimes called “goat” or “sheep” fence which appears to meet requirements F03, F04, F05 and F06.  My neighbor on the other side of the property has a small herd of goats and thus I assume would appreciate this.  There is some old farmer saying that says there is no fence good enough to keep goats in, but you can try. To state the strength I believe 12 1/2 gauge wire should be sufficient to meet requirements F04 and F06.  Also if we go heavier the 12 1/2 gauge it appears to impact the longevity of the galvanizing.

H-brace-1024x680

H-brace From Nash Brothers fencing

Corner and brace post will have a diameter of at least 8 inches.  Brace post will also have 8″ diameter.  Line post will also have a diameter of 8 inches.  Corner braces range from an H brace, N brace or a brace with a wood post at the top and wire stretching from the top of one post down to the bottom of the other. Anyone with an opinion on bracing please provide your input in the comment section below.  There are some sites that suggest the N brace is better than the H brace.  My neighbor seems to like the H brace because it looks better and she says “most installers do not know how to do a N brace correctly.  Also one of the common mistakes of fencing is not setting corner braces deep enough.  A guideline he follows: “The depth in the ground should be equal to, or greater than, the height of the top wire.”  This would indicate the H-Brace will be set 48″ into the ground.  This means the Corner post will need to be 9 feet in length to have 4 feet 6 inches above ground.  Wow that is much deeper than I expected.

N-brace2-1024x547

N-brace From Nash Brothers fencing

We are not trying to keep deer in or out with this fence alone thus a 4’ high woven wire fence seems approximate to meet requirements F01, F02, F03, F04, F05 and F06. It appears that most animal predators go through, under or around fencing, not climb them. To keep predators and domestic animals that tend to be low, it appears we want to install a strand of barbed wire along the bottom of the fence. This is a “derived” requirement from F03 and F05. Some people call this a “rust” wire. We can also install a strand of barbed wire along the top.

Note a single strand of barbed wire on the top of a 4’ fence does not meet requirement F10. It is not a significant deterrent to a human intruder. However it does a very good job of denoting your property line and it is a barrier to entry which should support your case of self-defense and / or Castle doctrine. If someone has to climb over a fence it is not like he did not realize he was trespassing.  To build a better perimeter fence to keep human predators out we will go back to our military training and buy enough coils of razor wire, but not install it. Razor wire installed a couple of feet back from the barbed wire topped woven wire fence appears to work fairly well. Cut through the perimeter fence, and then you will need to cut through the razor wire. Again, this is not to be installed during “times of peace” and will not be covered here.   An additional note here. I have noticed in my part of the American Redoubt there is this unofficial but well known warning of an orange fence post. It appears that people will paint one or two fence post (also sometimes trees) along a line of wooden fencing to indicate no trespassing, and no hunting. It is a separate question if you should do this, but it is done.

H-Brace0To achieve the requirement for the longevity of the fence the posts will be treated hardwood post. Choices seem to cedar and pine. Cedar wood is more rare and thus more expensive than pine. However cedar appears to stand up better than pine over time. This fact coupled with the comparatively low required maintenance appear to make it a smart investment. One strong suggestion is to ensure the wood post are pressure treated to American Wood Protection Association (AWPA) specifications.  The purpose of this treatment is to help the wood resist water.  It is simliar to coating the fence itself in zinc. I am completely neutral on creosote in perimeter fencing, but from reading many people suggest creosote is not what it use to be.  Thus I am simply going with a AWPA treated wood, that is also warranted by the seller for 30 years at a minimal.

Depth of fence post.  The corner braces should be equal to the height of the top wire, for us approximately 48″ deep.  The line post should be set “below the frost line” in our local area.  If not, the ground “spits the post” out of the ground the first freeze which is most likely what happened to our existing fence.  This would suggest at least 3 feet and perhaps 4 feet deep.  I will need to call the local agricultural-supply store to get a feel, but for our water and return lines they needed to be four feet deep.  Because this is an “overbuilt” or “defensive” homestead I set our solar well main water lines 8 feet deep.  I do not want a problem when there is no one to fix it.

fence-footing0To build a sturdier fence it should be buried 3 – 4 feet (below the frost line in our local area) into the dirt. Also you can look at concrete footing for all post, not just end post. This will help to address requirement F11. The problem with concrete footing is drainage away from the wood post. To meet this, put down a layer of gravel (and gravel dust to improve compacting) under the concrete.  Please remember the concrete should be installed below the frost line and wider at the bottom than the top or once again it will be spit out.  In addition to crushed stone / gravel at the bottom to help with drainage, you can also seal the bottom of all fence post with an additional treatment. The area of treatment should extended above the ground, thus something along the lines of 2’6” For an ultra long-lasting treated barn pole or fence post, zone coat the wood at the ground line with long lasting polymer wood coating. It also appears that some have used rubber sealant.

Thus the design to meet the SOW could read as follows.

Purchase Class 3 galvanized 12 1/2 gauge woven wire fencing. Fencing will be 4 feet high. The woven wire fencing will be 4”x4”spacing or “goat” fencing. Install a line of barbed wire at the bottom of the fencing or “rust” wire and a separate barbed wire along the top to discourage larger animals from leaning on the fence. The woven wire fencing will be stretched to follow the contours of the ground. The bottom barbed wire will be within 2″ of the ground. The woven wire fencing will be within 1″ of the bottom barbed wire. The top barbed wire can be within 4″ of the top. The fencing will be stabled to the posts.

The post will be round cedar wood post pressure treated to AWPA specifications and warranted for 30 years. The bottom 2’6” of the post will be coated with a polymer wood coating. The color will be brown. The post will be installed 1’6” into the ground. To accommodate 4’ of woven wire fencing, one barbed wire at the bottom and one at the top the fencing will be 6’ long . All post will be at minimal 8 inches in diameter at the smallest point. Post will be installed every 10’ of fencing.

Corner post will have a diameter of at least 8 inches. Brace post will also have 8″ diameter. Line post will also have a diameter of 8 inches. Corner braces may be an H brace or N brace. Do you have an opinion on bracing?

Please let me know how to improve this document on fencing in the comments below.

References:

A Christian homeschooling homestead.  Good goat fence.

Mother Hearth News Types of fencing

Home Place Earth Homestead Fencing

Sheep 101 Fencing

Wiki How Fencing article

Agri-Supply Creosote

Nash Brothers Fencing

Gulf Coast lumber

Beef Magazine Fencing

Hallman fencing article