Ledger to cinder-block w/o access to back

[dschad]

Hi all,

I was wondering how I should attach a deck ledger to a cinder block wall which I am unable to get to the backside of (so I can't run carriage bolts/backer board). Code requires 3" penetration of lags/sheilds into concrete for ledgers, but for cinder block we don't have the much depth (ie. the blocks are only 1" thick). Should I poke holes in the blocks and fill them w/ concrete? Any other suggestions?

Thanks very much,

don

[Rich]

Shanley will probably have a better idea than I do. But if the blocks are not filled I would suggest filling them by some method. I have seen a "wing" type expansion anchor for masonry - but not sure if it was intended for bearing or if it was only for pullout.

[roger g]

A couple of things: Obviously the code is referring to poured concrete wall but there must be something about block walls. It must suggest the c/c of these 3 inch deep anchors, how about a closer c/c but less depth?
A company Hilti makes all sorts of products that inject into a cavity wall and expands holding the anchor. Works great but pricey.

This is not an uncommon problem. I personally would use ordinary anchors closer together. The shear strength of an anchor even at one inch is enormous. Check with building inspector. It shouldn't be a big deal.

Roger

[Shanley]

Popping a hole in the course above (if possible) at each cell and filling the cell solid, as Rich suggested, with fine grout is the tried and true method. When the grout cures enough, typically aday or two, use expansion bolts to ancher the ledger.

[dschad]

Thanks to everyone for their input. It's a great help.


don