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Setting fence post on slopes

I am considering putting pre made picket fence panels up in my yard. The area has a slight slope and I am new at fencing. I want to use the step down method for attaching the panels to the posts. My problem is that the post that I purchased have the finials as part of the post. I am not sure how to calculate the depth of the posts for the stepdown and the placing of the panels.

Help is appreciated.

Re: Setting fence post on slopes


If you're new to fencing, then you're starting off with a pretty difficult project. Since you're planning to install prefab panels, then all your fence posts not only have to be straight up and down, but they have to be the right distance apart. And, on top of that, you say that your fence posts have finials on them, which means they have to be set the right distance into the ground as well.

As a DIY project for a new fence builder, you'd be much better off to make an easier fence:

1. Buy the required number of pressure treated 4X4's to run the length of your fence.
2. Set the two END fence posts first.
3. Take any scrap piece of lumber (like a piece of 2X4) and cut it into 3 pieces so that you have three pieces of lumber that are all the same thickness.
4. Attach one piece of that scrap lumber to the same side of each of your two end posts. Keep the third piece as a "guage".
5. Fasten a tight string between the scrap pieces of lumber on the end posts so that you can use your guage to tell when each intermediary fence post is in a straight line with the two end posts. That is, if the scrap lumber is 1 1/2 inches thick, then use your guage to ensure that each intermediary fence post is vertical and 1 1/2 inches away from the string. That way, if any fence post isn't vertical and causes the string to move out of position a bit, it won't affect the positioning of all the other fence posts.
6. Keep the distance between your fence posts less than 8 feet (use 7 feet, 9 inches, say) so that you can buy standard 8 foot length lumber and cut it to the right length to make the rails between the fence posts. No one will notice that the posts aren't exactly 8 feet apart or that the distance between one pair of posts is 1/2 inch shorter than the distance between another pair of posts.
7. Either:

A) Predrill 1/8 inch holes and fasten your rails to your posts and your pickets to your rails with coated deck screws. (These screws will have a flat head, so you'll also need to buy a 90 degree countersinking bit and countersink each hole to accomodate the conical shape of the screw head.) You can buy X-tra long drill bits at any place listed under "Fasteners" or "Machine Shop Equipment & Supplies" in your yellow pages phone directory. You can also use drywall screws, but they won't have a corrosion resistant coating. You can also buy stainless steel screws as long as you don't need screws longer than 4 inches. Use a variable speed reversible drill and a driver bit to drive the screws.

B) If you want to use a hammer, have a helper hold a heavier hammer on the opposite side of the fence post or rail as you nail something to the post or rail. The impact of your hammer blow will cause the hammer opposite to jump away from the post, but the post itself won't move at all in the process and the nail will be driven in just as though the post was securely in place so as not to move. (think of the swinging metal ball desk toys where the two end balls bounce, but the intermediary balls don't move)

C) Do your fastening with a rented pneumatic nail gun. These guns shoot the nail in, and it's the inertia of the post that prevents it from bouncing around as the nail goes in.

8. Now, attach horizontal boards on both sides of each fence post and use a circular saw with the blade set at an angle to cut a "/\" shape into the top of each fence post.

9. Have some heavy gauge (3/32 or 1/8 inch thick) steel plate cut and bent to make little "roofs" for each fence post that you can attach with a construction adhesive. MOST of the wood rot that occurs on fences is because people don't use pressure treated wood and because they allow gaps where rain water can collect. By putting a roof on each fence post to keep the rain off the post, your only worry will be rot between the posts, where the wood is much easier to replace.

10. Paint the fence and use caulk everywhere where rain water or snow melt could conceivably get in between two pieces of wood.

You're better off to make a simple fence of the kind described above than you are spending a pile of money on prefab fence panels that are gonna cause you nothing but grief because you don't have the experience and expertise to do the necessary excellent job setting your fence posts super accurately.

Hope this helps.

Re: Setting fence post on slopes

Basically, Nestor is correct and he has his method of building a picket fence.

I'm in the middle of building a 240 linear foot custom redwood dogear fence around a piece of property. The lot is flat, so I don't have to deal with a slope. All the treated 4x4x8 posts are already in 2' concrete. One side, about 90 ft, is already finished.

Building a wood fence is not for most DIY. Building a wood fence on a slope is not for any DIY. Even for those with all the tools.

Xsassygirl, materials are too expensive to ruin. my suggestion is to hire a handyman with experience.

A. Spruce
Re: Setting fence post on slopes
xsassygirl wrote:

I am considering putting pre made picket fence panels up in my yard. The area has a slight slope and I am new at fencing. I want to use the step down method for attaching the panels to the posts. My problem is that the post that I purchased have the finials as part of the post. I am not sure how to calculate the depth of the posts for the stepdown and the placing of the panels.

Help is appreciated.

You're actually thinking about it the wrong way. You need 1/4-1/3 of the post in the ground to adequately support the fence above ground. For a 3' tall picket fence, that's 12-18", 24"-30' for a 6' fence. If you're going to step, you're not only going to need a little more in the ground, you're going to need more above to handle the offset. Are these posts going to be long enough to do what you need?

How are you planning on accommodating for the slope and how much slope are we talking about (i.e., how much rise for how long of run )?

Re: Setting fence post on slopes
Re: Setting fence post on slopes

I am installing a fence on my property. I decided to go with the stepped fence, mostly because I think it looks better than racking.

while you only mention how to step, I'll insert a few other tips I've learned while putting in my fence, hopefully they'll save you some time and headache.

basic tools:
1. garden stakes (if you have very steep hills, you might need to point & cut a 2x4 in half. )
2. line level
3. string (I use masons string)

also keep in mind, you want a straight fence, so the string line will help keeping the fence straight from point A to point B.

drive a stake into the ground on the "outsides" of the fence area. (i.e. if you were looking at the fence the stake should be to the left of the first post, the right of the last post). Level the line using a line level. Initial height of the string line doesn't matter. I prefer having mine at about 6" to 12". this keeps it off the ground and interfering with level.

once you have the line leveled out, measure the distance from the ground to the string where post 1 is, and repeat the same for the end post. subtract the difference. This is your rise. Measure the length of the string line. This is your run.
( example: I installed the string line at 6" off the ground. I then measured where my first post was going to be, it was 6" off the ground. The area where last post was at 26" off the ground. This gave me a 20" rise.)

figure out how many sections you have to install. take the 20" rise and divide by the amount of steps you want. (example: over 120' and a 20" rise, I decided to step my fence in sections of 3. To do this, you take 120' or a total of 15 sections and divide by 3. This gives you 5 4" steps.

assemble one section on the ground, I laid down 2 posts and a panel, measure from outside of one post, to inside of the next post. This is your total O.C. width. measure just the post, and divide that by 2. Add this value to the O.C width This value will give you the center point of the next post. (example: I measured outside to inside, and my total width was 8'1", for 5" posts, I had to add 2-1/4" to the O.C. so a total of 8'3-1/4" is the center point)

I also measured from the top of the post to the bottom of the panel. I was advised to keep the panel 2" above the ground. This means that the post has to be 6'4" above the ground. mark a mark here. Now, measure the other end of the post, that's the depth you need to dig.
(example: in my setup, the post was 2" above the top of the panel, the panel was 6' high, and I was advised to keep the fence 2" above the ground. This gave me an overall height of 6'4". as my posts were 10', I had to dig 3'8" into the ground plus 2" for stone dust, this put my post 3'10" into the ground. )

NOTE: as my string line was 6" above the ground, my height from the string line to the bottom of the hole was a grand total of 4'4". This will save you from having to lift the post into place a dozen times to figure out if you're at the right level!

the first post is the key post. Take your time with this one, if it's wrong, even the slightest bit, the differences will carry throughout the fence.

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