Read More: Vinyl Fence System Overview
When it comes to installing vinyl fence across uneven terrain, there are a two options available. Assuming you are trying to follow the grade, you can either "Stair-Step" the panels, or "Rack" the panels out of square. Both methods are described in better detail below:
Racking Vinyl Fence Panels
Racking is the preferred method providing the grade change isn't too drastic. The reason for this is that you can utilize the pre-routed posts, and simply install the fence so that the top and bottom rails are out of square, but the posts and in-fill pickets or panels are plumb.
Our vinyl fences fall into three major categories:
Privacy Fence - Most difficult to rake, and smallest range, though can be done providing there are no accents on top. Total range is 3" over section width.
Picket Fence - True Picket Fences can rake quite a bit. If you chose a picket style with closer spacing, the range will decrease to about 2" per foot(approximately 18") per section.
Post and Rail Fence - Post and Rail fence is can follow terrain at a rate of 2" per foot (approximately 18") per section.
Note: These are the limits of the materials without a lot of fuss, or what we like to call the "natural" racking ability.
For sharp racking, outside of these guidelines, the routed holes in the posts may need enlarged on their heights to allow the rails to slide in at the additional angle. This can be done with a coarse file. Angles 35 degrees or more are possible with special posts and cutting.
WARNING: Pre-fabricated gates will not rake. When installing, make sure to hang the gate from the high side of the slope. It may be necessary to fill in with dirt or gravel to close the gap between the bottom of the gate and the ground.
Stair-Stepping Vinyl Fence Panels
This view shows the "stair-stepping" technique that is used to maintain the close distance from the bottom rail to the ground. In this case, order end posts instead of line posts so you can cut the second side on site for a custom fit. This is much more labor intensive, and depending on how drastic the grade change is, you may need to order longer blank posts and custom route both sides to match your application.