Foundation connection for ICF/frame/panels

Hi all, first post here, I need some advice. I joined the TFG recently looking for general information as I'm helping an established framer building a new home, but this one has me stumped.

The foundation of my house is flat-wall ICF's (not installed yet). I am planning the frame to be flush to the outside of the concrete (not the insulation) and the SIP panels would be simply hung on the outside of the frame. At least, that's what I was told to do by the framer, but I tend to disagree - I don't think that the lag screws will support all that weight. What should I do to make the connection between frame/sill and panel/frame? Ideally, the sill plate should be wide enough to support 100% of the panel and 100% of the frame, but short of making my foundation wall 14-1/2" thick, I haven't a clue how to accomplish this correctly and economically. And, I don't want to make a major mistake.

I've asked a number of architects in my area about this, and none have been able to help, so I turn to the Guild, who I know have the answers.

Actually, as I'm typing, one idea was to simply use a 2x14 sill plate and support all but 1" of the frame. Is that feasible?

Thanks,
Jon

Some ICF's incorporate a brick ledge, don't know if that would do you any good. You could pour an integral pier inboard @ the post locations (a hassle I know) & rest the panels in the ICF wall.
I would think in any case you'd need to transfer your shear loads to the concrete in some fashion, assuming you're using the panels for shear.

Some drawings might help. In today's market you can get SIP's that are only 4.5" thick and still present R25 or better when you add the internal drywall and any reasonable exterior finish (siding, stucco or whatever). The SIP's usually are installed on a 2x toe which is firmly fastened to the sill plate. Don't forget the closed cell foam air dam under the toe. About 1/2 of the outer thickness of the SIP plus the exterior finish is outside of the outer edge of the sill plate. You may want to consider offsetting the inside face of the SIP's from the outside face of the posts by 5/8" for later insertion of drywall (added insulation and ease of finishing).
This same SIP vendor will include plastic conduit for wire chases and/or a sprinkler system built to your plans and formed inside of the SIPs from the get go.Window and doors are now "standard" thickness jambs. Saves hours and lotsa routing/foam filling you don't have to do. Send me an email for the company name. They advertise in TFG publications. The outer face of the ICFs can be protected with 1" high density panels and an elastomeric coating forever waterPROOF below grade, especially if you add the proper compound to your concrete mix (cost about $30 per 5-7 yard load). This additive changes the crystalline structure of the concrete as it cures so it is also forever waterproof and will not effloresce over time. Anchoring the post bottoms offers several alternatives. If you are in an active seismic area you may want to consider reinforced concrete columns in the foundation walls all the way to the footers. If the floor joist system sits on top of the foundation then a "box" around the post bottom is an easy setup. Further horizontal and vertical movement of the posts is inhibited by lags thru the band and floor joists.
This is one of several methods that work.
Work safe, have fun.

Hey jon,

Well i just had to cross a similar bridge. I poured a conventional 8" thick foundation wall. We formed it up to match the exact footprint of my house. What i should have done is set the forms 1" wider ( if the foot print is 24' by 36', make it 24'1" by 36'1")all the way around. So in turn you would have a 1" lip of foundation wall to rest the panels on, which is plenty strong. Those panels don't way that much and after nailing them to the frame every 6" to 8" inches there isn't that much of a load bearing on that lip .
That is what i should have done looking back on it, but what i did to remeady the problem is set the p.t. sill plate over the edge of the foundation 1". So i would have a lip to rest the panel on. It doesn't have to be wide enogh to support the whole panel. Just enough to give you some relief and those ring shank nail are TUFF (or you mentioned screws). After the panels are attached to the frame they should move anywhere. That is just my two cents. I am building my frame up here in Randolph if you ever want to come up and take a look. take care Zac

I just completed a frame with the same situation. I just got some 4" angle iron in 2' lengths and predrilled (3)3/8" holes in each: 2" from each end and one in the center. I did a conventional first floor frame so I bolted through the ribbon and joist headers using large fender washers with star locking washers as well. I mounted these all around the perimeter with 2' spacing between them. I just had to remove the sheetrock where the brackets fell so they would tighten up against the foundation and sill. I could still tar the inset pressure treated 2x4 on the panel bottoms and lag up through the lip to them. It worked great and 3 years later there are no signs of any sag. Using a light weight siding material is probably a smart move. I used vinyl shakes; it looks awesome.