Before you start building your fence you need to lay out the area properly to get a good idea for where the fence is going to sit in proportion to the house and surrounding area.It can be helpful to run string lines at the elevation that the fence will be at in terms of its finished height. You can run these string lines both at the top and at the bottom of the finished height of the fence.
You will also want to spray paint the ground where the fence will be installed so that you can see where the post holes will need to be dug approximately. This can help you to determine any potential difficulties that you may encounter when actually installing the fence such as obstructions or grade issues with the property that you will need to account for in the design stage of your fence.
Setting the posts in place for your fence is one of the most critical components of the project. If the posts are not set correctly or are set out an angle or offset slightly the end results will be very noticeable in the Esthetic of the fence. Be sure to double and triple check your measurements before committing to digging your post holes. You need to be sure that you have even spacing of the post holes in that you have accounted properly for any intrusions such as the gate on the fence. Also you must consider the length of material that you’ll be using for the rails or stringers in the fence. The rails of the fence are the horizontal pieces that you attach the fence boards themselves to. If you put the post holes too far apart the stringers will not be long enough to reach from one post to the next. This is one of the most major problems that you certainly want to avoid when installing your own fence. The spacing for your fence posts should be equal so that is a quick and easy way to double check your spacing but nothing is a substitution for proper measurement with the correct tools.
When it comes time to dig the post holes you have a few different options. There are hand tools that can do the job however these require fairly extensive physical effort and should only be considered for smaller jobs. There are gas powered tools which can make quick work of even large jobs requiring many post holes to be drilled however this powerful machinery can be dangerous to use and has a bad reputation as being something that has the potential to cause injury.
It is regarded in the fencing industry that the diameter of the post hole itself should be 4 inches larger than the post. For example if you are setting 4 x 4 posts into place then you would want to drill and 8 inch diameter hole for the post hole.
The depth of the post hole is very significant as this will determine the overall strength and longevity of the fence. In the areas where the ground can freeze during the winter season. It will be extremely important to set the posts a minimum of 6 inches below the frost line. For all other applications. The post hole should be one third the height of the fence. For example a 6 foot fence should have a minimum of 2 foot deep post holes. If you were looking for an area that you can overbuild on this project. This is it. If you drill the holes and deeper than need be or use extra concrete. This amounts to extra cost and extra labor for your project but ultimately will result in a stronger, longer lasting fence.
When it comes time to mixing the concrete you want to be sure to follow some basic concrete fundamental working tips. Many people think it is acceptable to pour dry concrete into a post hole and then add water. This is not an acceptable way to mixed concrete. Concrete needs to be mixed thoroughly prior to placing and the amount of water that is used is of a critical importance to the overall strength of the mix. You should use at the minimum bagged concrete specifically made for post holes or general use applications or ideally mixing your own concrete using the 321 mix. The 321 mix is a very common concrete mix that includes 3 parts of gravel, 2 parts of sand and 1 part of concrete. The gravel is usually half inch in diameter in the sand is a sharp washed masonry grade sand. The type of concrete used for this mix would be called either type N, type 10 or type 1 depending on where you are located. All three of these concrete brands are exactly identical and the name changes only depending on where you are located. When mixing this concrete together you want to use the minimum amount of water necessary to achieve the desired placement thickness.
If you over water the concrete which is very easy to do this will result in concrete that has an exponential loss of strength. The concrete will require a month to reach its full strength. You can begin to work with the concrete in as little as 24 hours after placement given decent weather. In very cold weather allow at least 48 hours before resuming the remainder of the fence building project. During warmer weather or in the summer you can plan to be building the remainder of the fence 24 hours after pouring the concrete posts in place. As part of the post setting process it is critically important that you take the time to set up supports for your fence. If you do not set up supports for the fence the fence posts may slip out of plumb during the concrete curing process. If this happens you will come back the following day to discover that your fence posts are no longer plumb and square. This would require the removal and resetting of the fence posts. This is something that you want to most certainly avoid so taking the extra time to set up a system to hold your posts perfectly in place is a great idea.
Now that all the posts are in place and the concrete has cured enough for you to continue the project it is time for you to put up the fence stringers. These horizontal connection points between the posts are what you will mount the fence boards onto. You should use a minimum of two stringers for any size fence and as many as required to make sure that you have no more than a 24 inch gap between stringers. The method of attaching fence boards that you use will depend completely on the design and style of fence that you have chosen to build. Consider renting or using a pneumatic nail gun for the process of putting up the fence boards. Using screws is ideal however somewhat overkill for most fence projects. Using a regular hammer and nails causes a fair bit of trauma to the new fence and still only somewhat cured concrete fence posts. Using a nail gun for putting up the fence boards can be a huge timesaver.
As with any DIY project involving power tools be sure to use proper safety equipment at all times and do not attempt to work with any tool that you are not certain how to handle safely.