Any block masons here? How do you achieve running bond with 12″ CMU? The best I’ve come up with is to cut a 16″ down to 12″ when starting with 12″ (side of block) at corner.
My engineering calls for all cores filled and vertical bar in the corner plus a bar in core next to corner. Not any room for bar and concrete cover in that core next to corner when using 12″.
I can just move the bar to the next full core, but I’m worried about getting a full fill of crete in the corner core (and the next one) when pumping 10′ tall wall.
Make any sense? Brownbag? Anybody? Don’t make me draw a picture 😉
I’m trying to do it without using a return corner.
Thanks
Replies
http://www.consumersconcrete.com/products/concrete_masonry/standard/smooth.html
Use an 8...and then a 4 somewhere else in the wall. Stagger the 4's and it can be a feature or it can be hidden
I'm going for running bond right off the corner so that the cores in the block line up vertically (2 core cmu's). Otherwise I'd have a 4" 'overlay' in the bond.
First course 16 + 16 = 32
Second course 12 + 16 = 28 (4" overlay or whatever-not what I want)
So 12 + 12 = 24 minus 16 (first course) = 8 (yeah!) , but one of the cores is a bit stopped up for concrete flow.
Maybe I should quit worrying?
The whole wall is to be grouted or concrete filled by pump.
Seems (almost) like it would be easier just to form up an 8' high poured concrete wall. The footer would still be the same. Less work to form up a wall than lay up blocks, rebar same and fill all the cores with...concrete. Is there some reason for all of that block and grout?" Although I have the right to remain stupid, I try not to abuse that right"
Well I fibbed a little - it's 12' tall off the footing not that that changes anything.
I can't think of a good reason not to form and pour, except my engineerings about done. But it would be a simple change.
Most people use cmu here, so I was just following the herd. Hmmmm....
Nah.. I think its better in my area to use block - logistics?
Edited 11/24/2009 8:11 am ET by back2work
Huh?
I might be missing something simple or worrying too much about the core fill.
Only alternative I see is 12" hook corner, which (supposedly) nobody uses around here (and that ain't sayin' much!)
we did it on another job but I forget how, have to dig up some picture. to bad you cant just cut a 45
I'm trying to do it without using a return corner.
Why? That's what you need (also called a hook corner).
Yep. I think I just got some bad info from the block company.
I went there yesterday to pick up some different shapes because I was going to experiment with the drystack/SBC method. Sounds easy but I quickly learned it would be a nightmare (sorry drystack guys). It may work for a cistern or shed but I wouldn't recommend it for a house. Mortar would be a lot less work and less stress. I messed with it for a while and thought - thank goodness I tried this at home, cause I'd be screwed if I just went for it on the job.
Anyway I told the salesman I wanted a few 12" return corners with my 12" cmu just to see how it all goes together (I've only laid 8" cmu), and he insisted that they almost never sell any return corners on their 12" cmu jobs. That confused me, we argued a bit about running bond with 12", and I went home to figure out the "other way" to do the corners. Without the return corners. Sheesh.....
Where we're located suppliers do not make return corners for 12's (a.k.a birth control block). Running bond corners are achieved by using a regular 8x8x16 jamb at the very corner and alternating a "plug" piece of either a block face shell cut to 7 5/8" high and 3 5/8" wide or a concrete brick laid such that it flushes out the space between the 8" corner block and the adjacent 12" block.
If you Google a bit, you will find it drawn somewhere and it'll make more sense.
hmmm...
I'll look at that on paper. Are you putting the plug on the outside of the wall or in the inside corner?
Yes, the inside corner. It will alternate courses being left or right of the inside corner. The purpose is to provide flush surfaces outside and inside, and of course to provide bearing for the course on top.
Aha! We have a winner. Laid it up Brickies way - all cells open for rebar.
I would post a picture, but I get the feeling I'm the only one who didn't get it.
Thanks all-
Ok, here's a rough sketch, shown in plan view. Good Luck!
Every block plant around here makes 12" corners. Is that your only source for the block ? I would drive 50 miles to get some before I would monkey around filling that space on all the courses.
They seem to be the only one around. When I call around other counties it always ends up being part of the same company - and they refer back me to these guys in my area.
I know they have the return corners so I might get them. Same thing in one peice. The guy just threw me with the "nobody uses return corners" bit, so I started messing around with 12 x 12.
They don't like "walk-ins" so I probably just pissed him off from the start.
They don't like "walk-ins" so I probably just pissed him off from the start.
Don't worry, a couple more years of this economy and they will hand you a cigar and a drink when you walk in the door!