The actual process of fence construction varies with the type of fence that is being erected and the person who is building it. Some huilders prefer to set all of the posts in place and then attach the other parts. This is normal procedure for fences that have butted rail joints (such as wire and woven picket fences) and for those that have their posts anchored in concrete As another variation, posts and rails can be put up at the same time where the rails and posts must hr fitted together with an interlocking joint. If rails are joined in this way to concrete-anchored posts. it is important to attach them below the concrete hardens Other fence builders prefer to assemble the fence In sections, filling in the rails and pickets wheneser two line posts are in place. This method is used for many of the prefabricated fences and for louver and board fences when sections are built on the ground and then lifted into place. Fence building can be divided into three
stages the relative!) easy, preliminary stage of plotting the fence; the more difficult stage involv-ing exact alignment of the holes and of posts, and the third stage of adding the rails or stnngers and siding_ Each of these stages consists of a number of specific steps Working within this framework, you can tailor the procedure to lit your specific situation,
PLOTTING THE FENCE
The first practical step in building your fence is plotting its exact course and marking the line with stakes and string. If the fence is located on or next to a boundary line, it is wise to have an engineer or surveyor lay out the comer stakes Although such a survey will cost you a small lee. it will be much less than the later cost of shifting a sturdily built fence.
Of course, If your original survey stakes are still in place marking the boundaries of a newly surveyed lot. you might feel safe in using them for the fence line. Also, if the description of your property is exact enough in your deed, you might be able to measure out the lines yourself. How-ever, if you do so, you would he wise to enlist the cooperation of your neighbors to avoid any pos-sible misunderstanding. (If there are any remaining doubts concerning the location of the boundary in your mind, it might be a good idea to set the posts 6″ inside the line just to be safe.) Once you have established the end and corner points of your fence, the procedure is simple. You will need a long measuring tape, preferably steel; a carpenter’s square; a ball of mason’s twine, or any tightly-twisted string, such as discarded fishing line; some stakes; a hatchet; and a piece of colored chalk. Here are the steps to follow: 1. Mark the end or corner points with a solidly driven stake, if each point is not already staked. 2. Run mason’s twine between the stakes, draw it tight, and tie it firmly to the stakes. If bushes or other obstructions are in the way, use tall stakes so the twine will clear them. 3. Locate the sites for the remaining posts and mark them with stakes. There are several ways to do this. You can simply lay the rails in line along the ground between the end stakes and drive in a stake wherever they butt against each other; or you can measure the intervals with your tape, either laying it along the ground or measuring along the stretched twine. If you have a very long fence, like a country fence, you can plot its course by sighting stakes through a simple peep sight. Drive stakes (with tops painted white for better visibility) at either end of the planned fence line. Then make a peep sight by drilling a small hole in a board. Line up the end stakes by sighting them through the hole, and have a helper place the in-between stakes at your direction.
DIGGING, SETTING, AND ALIGNING THE POSTS
There are several accepted methods of rigging post holes, setting the posts, and—what many consider to be the most difficult problem in build-ing a fence–aligning the posts.
Digging Post Holes
The size of the post hole you dig depends upon the kind of soil, the height and weight of your fence, and the stresses it must withstand. If the fence Is to be a wind barrier or an animal enclosure, it has to be stronger than the ordinary boundary fence. Height is the primary consideration in determining how deep to set the posts. A good rule to follow is to sink posts at least I/3 of their length into the ground (thus you would use a 9-foot post for a 6-foot fence and sink 3 feet of it). Terminal posts (end, corner, and gate posts) need more support and are normally set deeper than line posts. The bottom of the post hole should be wider than the top to provide a better, more solid base. Moisture should be able to drain past the bottom of the posts, so the hole should be 4 to 6 inches deeper than the posts will be set so that the bottom may be filled with rocks and gravel. You’ll need an even larger hole in clay soil than in loose sandy soils. If posts are to be set in concrete, excavate 2’h to 3 times the diameter of the post.
SPACING OF POSTS
Unless you are installing a prefabricated fence where you must work with a predetermined post spacing, you will probably want your posts to be evenly spaced. It is also a good idea to make the most economical use of standard lengths of rails (normally 2 by 4s). Normal residential fencing calls for spacing of not less than 6 feet or more than 9 feet between posts. Where it will work with your fence design, try to purchase rails at least twice the length of the post spacing. In this way you can nail the rails so that the ends fall on alternate posts (as illustrated), offering a much stronger fence.
PLUMBING & BRACING THE POST
After the post hole is dug, shovel four to six inches of gravel into the hole and set the post on top of it. Then fill in as much gravel or soil around the post as is needed to hold it upright. Tamp the soil or gravel firmly while filling. Then true up the post by one of the following methods before filling in the remaining earth or concrete. 1. Check the two sides with a carpenter’s level. 2. Check with a plumb bob. Suspend the bob from a string attached to a nail driven into a corner of the post, as shown in the drawing. By matching the bob line against the corner line from two directions, you can ascertain if the post is plumb in both directions.
Once the post is plumbed, it should be braced to hold it temporarily in position while construc-tion proceeds. Strengthen it with outrigger braces, one end nailed to the post, the other embedded in the soil and bolstered with a stake. Check the post alignment again, then fill in the hole with soil, gravel, or concrete (see below). Tamp the gravel solidly in place. Leave the braces attached until after the rails have been nailed on. The bracing will help the post to resist the shock of nailing.
ADDING RAILS AND SIDING
Once the fence posts are up and firmly embedded, the hardest part of your fence building is over. The next step is to carefully attach the stringers or rails and siding (pickets, boards, grapestakes, or other materials) to the posts. If the stringers or rails are not attached firmly and squarely to the posts, all of your painstaking work in lining up the posts will be wasted.
Joining Rails to Posts
There are several accepted methods of fastening rails to posts, depending on the type of fence under construction and on the durability desired in the fence. The first step, regardless of the method chosen for attaching the rails, is to apply paint or preserva-tive to all surfaces where the rails and posts touch, for protection against decay. If paint is used, brush a generous coating of good quality base paint on both rail and post and attach the two while it is still wet. When the paint dries, it will seal the crevices. If the fence is to be left unpainted, coat the sur-faces with a colorless wood preservative .
Lap joints. The simplest and commonest joint used in attaching rails is the lap joint. The rail is merely laid against or on top of the post and nailed in place. Top rails are commonly attached in this manner, even though the bottom rails may be attached by some other method. Rails lapped against the side of the post are not strong enough to support heavy weight, because most of the strain is carried by the nails. For this reason, rails attached this way are usually used only to carry light pickets or are used by themselves, as in a post and rail fence.