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Aaron…Can you temporarily attach (or prop up) your ledgers to the ICF before your pour the concrete and then drill for your anchor bolts with the ledger in place? Remove the ledger, install the bolts, pour the concrete, and replace the ledger? No need to transfer the bolt locations with this method. (You can also replace the ledgers with the bolts in place, then pour. This has the advantage of keeping the mud from coming out around the bolt holes.)
Also, the last time I suggested to an engineer countersinking washers in a bearing beam, he advised against it. Why do you feel it is necessary?
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I have done several ICF foundations with ledgers. We cut 6" diameter holes in the styrofoam behind the ledger at each bolt location. This helps the bolts maintain proper shear strength having the concrete directly behind the ledger. The ledger is held in place with the bracing system and the bolts are installed in the ledger with nuts and washers already in place. The foundation is poured, the bracing stripped and you are ready to start hanging joists. Several things to be careful of. Let concrete set for one week before tightening bolts, Layout your joist locations before cutting or drilling any holes. This will eliminate the problem of having bolts and hangers trying to occupy the same space. Make sure the ledger is supported by the bracing system down to the footing because ICF form systems settle when concrete is poured into them.
Good Luck
*Aaron, if you need ledger boards you must be going all the way up with the same thickness. Why?I drop to 4" ICF walls above the basement if there is only one floor leaving either a 2 inch or 4 inch concrete ledge. A heck of a lot easier. Have fun.
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I just got back from an EcoBlock erection and pour that used Anchor Tunnels. A feature that was not apparent to me from the Web pages are a set of interrupted bayonet like fins on the side used to screw them into the foam. They work very well if the hole was made with a 6" hole saw. After seeing them and talking to the people from EcoBlock that were there, I have no reservation that Anchor Tunnels are the way to go for bolting lentals.
*Thanks for all the great posts. In retrospect, countersinking is probably not prudent. I think I'll hang the ledgers on the braces and mark the joist spacing, then let the nuts and washers protrude. Amen to cutting the foam out so the concrete flows to the back of the ledger.Aaron
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I'm going to begin building a new home with ICFs as soon as the SE Ohio clay drys up enough to come out of the hoe bucket. Taking an ICF structure all the way to the rafters requires attaching 2x12 ledgers around the full perimeter for floor joists. I've seens ads somewhere for a drill bit that will drill a 1/2" hole for the anchor bolt and countersink for an 1 1/2" OD washer at the same time, something like a Forstner "collar" on the chuck end of the bit. If you know of such an animal, please advise, will save much aggravation and bit swapping.
*You may want to check out the Anchor tunnel. It looks like a better way to mount a ledger to me, but I have not used them. Is anyone out there with real-world experience?
*Chris,I have seen them and have a few reservations. Is transfering the anchor bolt locations to the ledger easier than screwing the ledger to the ICF studs? Sounds equally tedious to me. Granted, would love to avoid PT ledgers.... Ditto on the real-world experience.
*I was thinking of using 1/4" plywood or something even cheaper to make templates. The template would position the J-bolts and be screwed to the ICFs. Then use the template to drill the ledgers after the pour. Overkill perhaps. Another option is to use the actual ledger to hold the J-bolts during the pour and incorporate it into the ICF bracing. This does seam more efficient and in line with the stay-in-place approach of ICFs.
*Aaron...Can you temporarily attach (or prop up) your ledgers to the ICF before your pour the concrete and then drill for your anchor bolts with the ledger in place? Remove the ledger, install the bolts, pour the concrete, and replace the ledger? No need to transfer the bolt locations with this method. (You can also replace the ledgers with the bolts in place, then pour. This has the advantage of keeping the mud from coming out around the bolt holes.) Also, the last time I suggested to an engineer countersinking washers in a bearing beam, he advised against it. Why do you feel it is necessary?
*Aaron, you might want to send this question up at the ICF-web forum; there's lots of helpful guys there: http://www.buildcentral.com/cgi-bin/ubb/Ultimate.cgi?action=intro