I need some advice. First a short intro - hubby and I are building a smallish icf house with basement out of EZ-Block,a foamed concrete block which is fireproof and screen grid form factor. We have a block wall in the basement center that will be floor and roof loadbearing, so our floor joists run perpendicular to this wall. When putting up the walls we didn't take into account lining up the verticle columns, which the icfvl-w we bought for ledger boards have to go into. Thus the icfvl plates are offset from the outside walls to the center wall and there is no way to attach the joist hangers without ending up with joist hangers OVER the icfvl-w ledger hangers on one side. We either tear down the center wall and rebuild, which won't really help because the verticle columns in the two outside walls don't line up either, OR nail/screw/bolt another ledger board over the first for the joist hangers to attach to. We would have to route out where each icfvl-w screw is since they would be proud of the surface. We're stuck right now trying to figure this out. Thanks for your time! Oh, adding that the icfvl is 24"oc, the joint hangers are 12"oc, and because the icfvl-w hangers are 7"wide there just isn't any way to make the hangers avoid the icfvl because of the verticle column offset...

Sounds like doubling your ledger is the most viable option at this point.

Since the intent was that that center wall would also support roof loads, I am assuming it has a fair sized footing under the wall? I guess another option would be to put up a stud wall on either side of the center block wall to support the center floor loads.

What is the span of your floor joists?

Yes the center wall has the same footing as the outside walls. On one side the 2x12 span 17' 4", on the other side 15'6". All 12" oc.


At this point unless we can double up the ledgers on each side of the center wall, we'll have to pre hang the single ledgers with j bolts and 2x supports under them before the pour...I'd prefer to use the icfvl and cover them with another board later to take the joist hangers...

You havn't poured this yet? I got the impression from your initital post that it was already cast in CC. If you havn't poured it yet, there may be another option, which would involve modifying the blocks a little. Basically you open up the screen grid to form a box crosssection at the height you are placing the ledgers. This is also sometimes specified to form lintels with stirrups over window and door openings in load bearing walls. By making that area a continous box of Concrete, you may then be able to place the ICFVL's wherever you need along the wall, to not interfere with the joist hangars on the finished ledger...

No, not poured yet, wanted to resolve this before we pour. The code officer is a real jerk (he railed against building anything out of the ordinary and everyone out here has problems with him) and we haven't called for an inspection yet, so I'm trying to avoid involving him until we have it fixed. I know what you are saying about opening it up but it would essentially leave the entire top row open to make the icfvl work since the vertical columns don't line up on either side...yes we had to modify for the lintels. If I cut away all the interior connections I would still need to put up the ledger boards on each side to hold it all together for the pour, and it would put a tremendous amount of "sawdust" down inside the walls....

I am not specifically famillliar with the block you are using, but is it setting down flush on the footing/slab, or is it resting on interlocking teeth? Many blocks are this way which leaves gaps between the teeth at the bottom and makes it easy to flush out any debris with some water. You could also cut out drain holes at one end and flush the debris to that end and out the hole, then foam the piece of cut foam back in place and strap over it to adjacent ties to keep it in place during the pour. Failing that, a shopvac would probably pull most of the "sawdust" fairly easilly using a piece of PVC pipe that can fit down into the wall past the rebar.

That is the problem with planning mistakes, they usually require a little sweat equity to rectify. As for doing this, Have you checked with the block manufacturer. They may even have some spec for doing something like this. In my experience, I am rarely the first person to make a particular mistake/encounter a specific problem. This sounds like one of those things they may already have a spec or detail drawing for

As for your building official, do your plans have an engineers stamp on them, or did you work them up using the prescriptive tables? If you consulted an engineer to analize your plans before submitting them to the building department for review, you should most definitely consult with them again for a change of this magnatude. IF you worked them up with the prescriptive method, you really need some input from the block manufacturer for something as important as the floor support. As long as you are following engineers or manufacturers details or changes, the building official however much he dosn't like it, should ultimately go along with it...

Good Luck.

We tried flushing out the block at the bottom when it got alot of dirt in it from a windstorm, we tried vacuuming, nothing worked except dismantling the walls down to the first row then rebuilding. Then we kept plastic over the walls until they were 6 feet high. I know we can't do that again. We are off grid and don't have water pressure so we bought a pressure washer but it didn't do squat to flush the walls.

Well the plans don't have much detail, except we had to get the outside basement walls engineered.

No engineered plans. On the plans, 2x12 joists are specified at 12oc. That's pretty much it for specs, other than a floor plan for radiant floor heat layout.

Small block manufacturer from Utah. We picked these blocks because they are fireproof. The owner recommended using the icfvl, but it turns out he never tried them himself so couldn't warn us about lining up the vertical columns on opposite walls.

Well if the manufacturer cannot help you, and you do not have a detail from them to beat the inspector into submission, it might be a good idea to bring the engineer back into it for the load bearing wall to floor attach detail to present to the building department.

As for flushing out the wall, if it has openings at the bottom, I found that large volumes of water work the best. My build site is sand, and had quite a bit of that find it's way into the wall along with leaves and needles after it was stacked. I poured in 5 gallon buckets, approx 1 per 5'-6' of wall length. This did a good job of flowing the debris out thru the openings for a good clean cavity before the CC pour...

Ok.
I was just going someone here knew if a built up ledger board was ok...without paying an engineer.

But thanks for all your time!

I must be missing something. What difference does it make if your columns don't line up? The icflv's are just to support the ledger board not the joists, right? If you hang the ledgers, you can then line up the joist hanger on each ledger to carry the joist. The ledger hanger and the joist hangers are independent.

The icfvl-w is 7" wide at the bottom, and the "ledger holder part" goes over the front of the ledger, with 8 hex head screws that stick out about 3/8".


Our joists need to be at 12"oc, while the icfvl is at 24"oc. The joist hangers are 3.5" wide. This barely works when the icfvl is lined up directly across from each other, but when they aren't, the front of the icfvl falls where a joist hanger needs to be.

This is why we either need to go to j-bolts on one wall or (easier) glue/screw/bolt another ledger board over the first to cover up the icfvl parts so they aren't in the way of the joist hangers.

I called the block manufacturer to warn him to tell others of this problem because, while he had recommended to me to use the icfvl, it turns out he had never used them himself, AND he is the one who started our walls to show us how to lay them, and he had never realized his way of laying out the walls would give this result. So this will helps others.

If the block were not screen grid we would have more leeway to move the icfvl around, but we are stuck with the spacing in the screen grid to imbed the icfvl.

If you are using solid lumber joist, it may be a problem. If you are using I-joists and top mount hangers, it is seldom a problem as you don't have to nail the joist hangers into the plate and the thin web of an engineered joist seldom interferes with the bolt heads or you can just notch that portion of the web without effecting the integrity of the web.

That said, we usually use J-bolts with 1/4 to 3/8" flags slightly deeper then the ICF panel. The backside of the flag is in bedded in the concrete and the front is in contact with the lvl to prevent any play or crushing of the ICF. The flag is welded on which also eliminates any moment issues on the bolt. We layout the joists prior to installing the ledger so we can get the bolts in where there is no conflict.

Yes, 2x12s. Just trying to avoid prehanging the ledger board or trying to drill holes and match up to j bolts after the pour. We're 69 and don't really want to put up and take down a ledger board to match up holes. Is we can't double up the ledger board (built up beam), like is done at staircase openings etc (doubled header) then prehanging the ledger with j bolts imbeded and supported from underneath seems easiest as a fallback...

I hear you but consider, putting up two ledgers is the same work as putting one up twice ;-)

We typically do 9' high basements so our strong backs are 9' high. We lay 1x4 cleats on top of the strongbacks to make sure they don't get trapped and then set the ledge board right on top, drill the holes through the ledger into the foam and then take it down, route out our slots and install the bolts in the ledger and install the whole works. As mentioned we already have the joist hangers on as it is easier to nail them on on the ground.

If your product doesn't use strong backs, screw a 2x4 horizontally at the line of the bottom of the ledger so you can rest the ledger on it while you are working.

I used ICF-VLs and just looked at them in my crawl space. I can see the problem putting hangers over them. Two thoughts/questions. If you double ledger your floor will be supported by the fasteners between the two ledgers, not the ICF-VLs. You largely lose the benefit of the ICF-VLs. I have serious doubts that any nails or lag bolts or whatever between the ledgers is going to be a strong as the ICF-VLs. I would say use the J-bolts as has been suggested. Another possibility, although I probably wouldn't do it, is to put the ledger board down the width of itself and set a second ledger on top of it. That way you get the full load carrying capacity of the ICF-VLs. It'll complicate wall finishing though.

Why are you using 2 x 12s rather than I-joists? I would think I-joists would be cheaper, and quite possibly stronger. It's been so long since I built my house I don't remember how they compare for stiffness and strength. My span is 26' inside the walls. I used full length 9" I-joists 16" o.c. resting on top of the center bearing wall. Easier and cheaper than hanging them from the center wall. My floor easily passes the "china closet test", i.e., if you jump up and down on the floor china in a cupboard doesn't jingle! If you do that you get away from the alignment problem. Take a hard look at using 9" deep I-joists the full span. If 9" isn't stiff enough go with 10". You'll save money, labor, and headaches. In areas of high load, like a Jucuzzi or shower with a concrete base, you can easily use a deeper I-joist or space them closer. Under my showers I used 5 1/2" deep LVLs 12" o.c. and supported on a extra pony wall so the span was shorter. Under the Jacuzzi the joists are spaced 12" o.c. but are still just the 9" deep ones.

If you're plenty computer savy download a beam program from Roseburg Lumber Co. That's what I used to determine my joist layout.