Replies

1. 
   florida | Jul 20, 2004 03:22pm | #1

   Pour the slab first then core drill for the fence posts. Much easier, quicker and the post can be removed later if need be. Around here there are lots of companies that will do the core drilling for you or you can rent a machine and do it your self.

1. 
   moosehead | Jul 20, 2004 03:56pm | #2

   What exactly is core drilling? Is it drilling a hole large enough for the fence post?

   Is it possible to simple fastener the posts to the slab with bolts?

1. 
   CapnMac | Jul 20, 2004 06:21pm | #3

   What exactly is core drilling? Is it drilling a hole large enough for the fence post?

   That's it exactly.  The drill bit resembles a pipe, with the cutting teeth on the edges.  This reduces the amount of material that is cut to make the hole.  They are usually water cooled, which also floats the chips away.

   You can bolt the posts directly to the deck surface, which may be an issue as you get close to the edge of the concrete deck (you can "run out" of deck to make a hole in).Occupational hazard of my occupation not being around (sorry Bubba)

2. 
   DANL | Jul 20, 2004 11:42pm | #4

   I'd vote for using bolts or some other fastener (there are lots available). Boreing holes sounds like work, and I'd worry about weakening the edge of the slab and allowing water to get in (where it might freeze) and casuing problems.

2. 
   Cole | Jul 21, 2004 01:48am | #5

   Instead of core-drilling just put in some pipe blockouts at your post location.  3 or 4 inch PVC pipe 4 inches long.  Alot cheaoper than paying for diamond wear on a core drill.   Or set weld plates every 6-8 feet to weld your posts to.

   Cole

   Cole Dean

   Dean Contracting

1. 
   Sphere | Jul 21, 2004 03:21am | #6

   soda cans work too..set the post and epoxy it in in the can. 

   Spheramid Enterprises Architectural Woodworks

   Repairs, Remodeling, Restorations. 

1. 
   hasbeen | Jul 21, 2004 04:06am | #7

   That's the kind of cost effective and creative thinking I love to see and to hear about!

   Thanks for posting, Duane.You're unique!  Just like everyone else!      Scott Adams

1. 
   Sphere | Jul 21, 2004 04:15am | #8

   well garsh, thank you.

   I had to install a handicap ramp at a shop I worked in down in NC.

   Realized that I needed a freakin rail as the concrete truck was backing up.

   Looked around and saw the trash can, fished out a few cans and stuck em in the wet mud..troweled right over the tops a bit.

   when broomed off and set, punched the can bottoms in and glued in the steel pipe that was supplied by the welder.

   slicker'n snot. 

   Spheramid Enterprises Architectural Woodworks

   Repairs, Remodeling, Restorations. 

3. 
   Bluemoose | Jul 21, 2004 04:55am | #9

   I might be inclined to set my fence posts and then pour the slab around them.  That would give you a really nice finished look around the posts and there won't be any coring involved.  I did this on a retaining wall once that was going to have a fence on top of it.  Set the posts and then when the pour is over, double check for plum.

1. 
   Sphere | Jul 21, 2004 05:08am | #10

   you two mooses related? 

   Spheramid Enterprises Architectural Woodworks

   Repairs, Remodeling, Restorations. 

4. 
   WayneL5 | Jul 21, 2004 07:32am | #11

   Of the three basic choices, put the fence posts in before the pour, form out holes before the pour, or make the holes after the pour, I favor the latter.  Marking out for fence holes and forming them up before the pour is really difficult.  There is too much chance of getting some of the holes off a bit, then the fence won't fit.

   You could install the fence first, but then the masons would have to work around it, which is more work, but not undoable.  The concrete will crack around all the posts, though, unless you sleeve around all the posts with round, resilient sleeves, such as styrofoam.  You could make such sleeves by core drilling some styrofoam 1" larger in diameter (½" on radius) to go around each post.  Even then, you risk cracking.

   The least risky method, both from cracking and layout, is to locate and install the fence posts last.  Drilling and bolting will work so long as you use epoxy anchors and not expansion anchors, but you will have a weak point, in that the angle brackets or whatever at the base of the post will not be all that strong.  The best way is to rent a core drill (machine and bit) and drill the concrete.  The sooner the better because concrete is much softer the day after the pour than it is a week later.  Needless to say, having the fence on site before the pour is a big help in ensuring accurate measurements and layout.

   You can't locate the posts too close to the edge with any method or you risk cracking.

1. 
   Handydan | Jul 21, 2004 11:56am | #12

   Try not to laugh to loudly, but I just got done putting up 78 feet of gulp, plastic fence, on top of a rock wall with a cement cap.  Somebody in the distant past had put brackets on top for 4 x4 posts.  Problem was of spacing, they planned on 8' centers, customeer picked 6' sectons of fence.  Used most of a box of Tapcons, but fence is ready for most use, and I only had to cut off two of the old brackets.  So my answer, pour, then set fence with plates on botom of posts and lots of little screws.  Get the hex heads, much easier driveing.

   Dan

5. 
   Davo304 | Jul 22, 2004 08:22am | #13

   Pour your slab, then have a mason lay up block/brick pillars "X" amount of feet apart and then attach your wrought iron or aluminum fencing to the pillars....will look very sharp!  The pillars will be attractive, stout and strong.  Most wrought iron and aluminum fencing on market today can be equipped with special mounting brackets that attach to such  pillars with tapcons.

   Just a thought.

   Davo

6. 
   shira_wilson | Sep 19, 2019 03:09am | #14

   You should consult a professional contractor as he can give you better advice regarding this.
   https://www.highqualityasphalt.com.au/