2

I have 2 metal poles 10 ft poles and a metal entrance gate that is 10 ft wide and 4 feet tall. I want to get it in the ground this weekend. I am going to rent a gas post hole digger. What kind of cement and how much do I need? I read somewhere that it is a quicker idea to pour the mix in the hole and 2 gallons of water on top of that.
Can I get a step by step directions on how to put this in the ground?

1

Depending on the weight of the gate and your climate gate post holes are dug deep enough so as to not be effected by frozen ground heave. If you are located in this type of climate than 48 inches should be your goal to avoid having the posts disturbed by frozen ground forces. If you reside in a mild climate than 18-24 inches will suffice. The diameter depends on the diameter of the post, but figure for a 3-4 inch post drilling a 5-6 inch round hole. To help keep the post from possibly loosening the last 3-4 inches of the hole bottom should be widened to form an undercut (or a bell shape) making it wider at the bottom. A gas powered auger will save much time and labor. You will still need a hand operated post digger to remove the last of the dirt. Be forewarned hitting a rock will be a jolting experience even with a clutch. Once you have excavated a post hole to the proper depth insert the post. It should be positioned (if you drilled exactly) approximately in the center. You should support the post so that it remains in position while the concrete sets or you make adjustments. Any length of lumber or rebar that is available will do. Attach two opposing braces close to the top of the post (wire will fasten to anything well). Using an appropriate sized level, check the post for plumb alternating from 90 to 135 degrees on the pipe circumference (side to side and front to back). Adjust the support brackets to keep the post plumb. You should have at least (6) 60 lbs. bags (or equivalent) on site to fill a 48 inch deep x 6 inch diameter hole. Mix two bags at a time in a wheelbarrow following the directions for the amount of water (I believe it's 2 gallons per 60 lb. bag). When completely mixed shovel into the hole. After every 4-5 shovels tamp the concrete with a 2 x 2 or 2 x 4 to compact the mix and remove the air. The job will be most successful if you mix and pour the concrete without letting it set up. Fill the hole so that the concrete is a few inches above grade. With a trowel round off the concrete so it tapers away from the post. Finally, don't forget to inscribe the date and your initials in the still wet concrete. You can remove the post supports the next day, but let the concrete set a few days before hanging the gate.

0

Most people pour a footing rather than using a post hole digger. The reason is that you can pull it out too easily unless you anchor it into the cement, and people can steal your gates.

  1. Drill a few horizontal holes near the bottom, and put rebar or longer bolts through them. These will anchor your pole to the cement.
  2. Dig large hole roughly 1 ft in diameter, and several feet down.
  3. Mix cement.
  4. Pour some cement into hole.
  5. Insert pole. Ensure that it is plumb.
  6. pour more cement around pole and remove air.
  7. Brace pole, and allow cement to cure
  8. Backfill hole
  • "Several feet down" being "at least to the local frost line", and remember to allow for that. Frost line here is 4' down, so when I got new posts for my 6' fence they had to be 10' long. (Or I would have had to pour a 4' footing, and use anchoring hardware to put a 6' upright on top of that.) – keshlam Nov 25 '15 at 23:45
0

If you are going to try and sink holes 4-6 feet deep, it may not be wise to try and do it this weekend, unless (as seems unlikely, since you didn't mention it) you have already called the local dig-safe (or equivalent) number to have underground services marked before you dig. If you hit something without having called and had things marked it's very, very expensive - normally if you've called and had things marked and there was an error or omission in marking, you are fine if you were digging where they said there were no services...

So:

  1. Call dig-safe, blue-stake, call-before-you-dig or whatever applies in your area.
  2. Dig holes - depending on what's down there a gas auger may or may not be all that helpful (they get unwieldy when they thread onto a rock, or run smack into one that's too big for them.)
  3. Set posts in holes.
  4. Actually mix the concrete - "dump in and add water" is going to make junk.
  5. Pour concrete in hole - plumb the posts and brace. Wait for a day.
  6. Backfill soil, tamping throughly every 6 inches or so.

If you backfill carefully (tamping frequently so the backfill is solidly set) you don't really need any concrete. If you want to use concrete, 2-3 bags of concrete mix per hole is generally adequate (or a bag (94 lb, 1 cubic foot) of cement and a few cubic feet of sandy gravel, mixed.)

  • Someone actually stole our gate when we didn't use enough cement -- they used a pickup and yanked it out. A large cement mushroom helps prevent that. – gbronner Nov 26 '15 at 0:00

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.