Reverse brick shelf for residential basement walls

[skeletron]

I'm looking for a bit of exposure to the flush framed floor detail that others are using. I've been going in circles trying to justify whether the reverse brick shelf (arch's quick sketch detail) is better/worse than either a top flange hanger to a sill or a ledger to the inside face.

Reverse Brick Shelf:
-Extra forming
-Kind of a crappy detail for anchorage and reinforcement. Top stem and lower shelf would be 4" wide ea. for 8" wall.
-Reinforcement less of a concern for low height walls (ex. crawlspace)

Top Flange Hanger:
-A little bit of a bump in the floor that may or may not be a big deal
-Cross grain tension for the nails into the sill

Ledger to Inside Face:
-Seems like the simplest detail...no extra formwork, ledger bolts could be CIP or post-installed

I would be interested in what the most common detail and rationale happens to be. I would also be interested in understanding if one detail provides a more acceptable "building science" (thermal break, capillary break, etc.) solution.

 

[DoubleStud]

Most common is just hang the joists. It seems the extra cost of Simpson hangers will offset the labor to make the shelf.

 

[XR250]

I have done it all three ways. I prefer the ledge myself for no particular reason other than it feels better.

 

[jayrod12]

We do the reverse brick ledge (as you call it, we just call it an upstand). Most of the guys don't complain unless they want to use ICF formwork. In which case we do either Simpson Strong-Tie ICF-VL hangers or top flange hangers.

 

[DoubleStud]

So more than likely this wall is reinforced in the middle of the 8" thick wall. Then what do you do on the top where the ledge is? Have another rebar in the middle of the 4" thick wall that is bent to tie to the main reinforcement? It is just another detail that concrete guys may miss and more field bending. Also now you need to make sure both elevations are correct. The bolt for the sill plate is embedded into 4" thick wall instead of 8". I like to keep my residential project simple and stronger. No doubt the full height wall is stronger. Lets say the floor ends up bracing the top of the basement wall laterally, you only have 4" of concrete resisting the reaction from the floor joist.