What I know now, having sweated through a Logix ICF build:
If you have spent any time working with Logix ICF, and in particular, designing a plan using their modular dimensions, tell me if you have noticed a bust in their design for the widely-used 6.25″ core block product.
Unless I am missing something, their product designers screwed up when designing the corner blocks with 16 x 32 inch legs (outside corner to block ends), with their overall block thickness being 11.75″.
With these figures, the corner blocks have inside leg dimensions of 4.25″ and 20.25″, and no matter how hard you try, you cannot get blocks to lay out to modularity if your building footprint is anything other than a simple rectangle.
Designing and building with ICFs is a straightforward thing. Or it should be. You work to get a desired footprint, length by width, bumpouts, bump-ins, corner jogs, one you know you will change a little when you adjust for block modules. Then you get out the manufacturer’s table for “preferred” wall layout runs, which gives the modular dims for outside-outside, inside-outside, and inside-inside runs. Then you make your adjustments.
The problem with Logix is that nothing can be made to “close” to modular figures, forcing you to skew a foundation or building off square. I hate doing that, and will never again use Logix.
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I'll try to illustrate the problem, for those that are still interested (I know, it's really boring), by showing some numbers.
This pic is a planview of a slightly smaller version of one we sweated through with Logix this past week. The dimensions shown are all modular with Amvic 6-inch-core blocks, which we'll use when building again. Amvic's product designers got it right.
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As a little math or design exercise, if you are so inclined, try to design the shape using Logix ICF. Here is the challenge. Beginning with the 8'-11 outside-to-outside dim at bottom, and continuing clockwise, the Logix runs that are close are as follows:
9'-4, 27'-8 1/4, 4'-4 1/4, 14'-8, 10'-4 1/4, 8'-4 1/4, 28'-8, and 28'-8. Using these figures and sticking with an 8" module, move the walls in and out as you see fit, to try and get close to the shape using Logix numbers.
You must stay modular using the 8" figure. For example, 9'-4 can move to 8'-8 or up to 10'-0, but nowhere in between.
It is an easy exercise with CAD, particularly Sketchup. I imagine it is tedious with calculator, paper, and pencil.
Try as you might, you cannot get there with Logix. I cannot imagine anyone working with Logix after the experience of one job. We sure won't.
Gene,
Obviously I know nothing about ICF as layout is concerned.
Wouldn't you just do as you would with CMU block and build up te cornes and cut the field block as needed to obtaint the correct bond stagger?
And how does (did) this other system differ other than it being 6" rather than 8".
Oh, wait; typing that I realize the problem. (I think)
You didn't figure that out ahead of time with all the extensive design you do?
I'm not trying to be a wise guy here, just trying to learn something.
Eric[email protected]
I have built with Amvic, but all blocks have the same issue. Left and right lengths of 90 and 45° corners are all different and also differ with core thickness. In an ideal world, you would adjust your footprint +/- a few inches so all the blocks interlock. This would have to be done based on the selected manufacturer and core size. Since this is almost never an option you end up with a vertical seam in the block where courses don't interlock. Just take a strip of plywood screwed onto webs inside and out and you are fine. Try to place the on-interlocked vertical seam above doors and windows.
I have modified a friend's layout so all blocks interlocked. The adjustment added one inch to the design length and reduced the width by one inch for full blocks, no cutting. That trick almost never works, but sure makes a smooth build when it does.
All that said, odd seams are not that big of a deal. I have 67½° Tee intersections for one wing. We just made up plywood and 2x corners, screwed them on and poured. Don't compromise what you want to accommodated your building material, but a little forethought can optimize material usage and labor with any building material.
The savings to build to ideal ICF dimensions vs. what makes the most sense design wise is usually minimal.
The most wasteful designs have very short jogs in the walls, such as 12" or 16", since corner blocks are expensive, much of the blocks are cut off and are harder to brace. Although if it makes the design look right I'll be the first to argue that the short jog should be kept.
What you're trying to do is like preplanning each turn in a copper plumbing system.
Beer was created so carpenters wouldn't rule the world.
It worked out OK. Thanks for your reply. We made the Logix fit the desired plan (which did not use the Logix "preferred wall lengths"). There are places where ribs don't line up, and we'll fight it a little at sheetrock time, but what the heck.
This pic was taken yesterday. First truck of mud is coming at 8 a.m., and the pumper is setting up before that. I'm out of here.
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Best of luck.
Beer was created so carpenters wouldn't rule the world.
Gene,
What's holding the 2 x 12's on to the ends of the pour? Plenty of strapping and fasteners I can't see, I hope.
Good luck man
Ron
The pic was snapped a couple hours before all the pre-pour work was finished.
We slapped on so much bracing and scabbing, it made the site look like a circa 1805 shipyard.
The pour, 8 a.m. to 10:30 a.m. yesterday, went without incident. No problemo.
Excellent! Congratulations!
I should have read your caption more carefully.
I kind of like Logix, myself. I see less of those little bulges between webs than with other systems and the wide open web leaves little for the mud to hang up on. Plus you get an extra half inch of insulation for a little less money.
Ron