Bolting through Masonry Veneer

[grogannc]

I have a client that wants to have a deck structure attached to the existing home through masonry veneer. Our actually specifies a bolting spacing through masonry veneer but as others have said, I am worried about putting any load through the veneer. I found this solution from a post in 2007 but was hoping someone could help me understand the concept a little better?

"For a brick veneer the deck has to be either free standing or it should be attach to the structure using wood or steel spacers at each of the through bolt locations. A 4x or tube steel spacer the depth of the veneer plus the cavity depth and plus 1/4" x 9" or 11" long is placed at each through bolt location (typically 24" o.c.). The ledger is solidly bolted to structure with two or three bolts through the ledger and spacer and band board. The brick veneer goes on past behind the ledger and is not loaded in any way. Its best if the predrilled spacers are temporarily held in place to the band with a couple of bolts while the mason does his work then the deck contractor can drill the ledger from the back side through the band to align with the spacer holes. There needs to be through wall flashing at each spacer location. Its good if the top of the ledger aligns with a mortar joint so the spacers are easy to flash."

Wouldn't the tube steel or wood have to be closer to 4" in actual depth, ie. a nominal 4x wouldn't work. Would have to rip a 6x to size. Or am I understanding this detail? This "deck" is going to have travertine tile so a lot of DL will be going into these connections, ie. no way I would just bolt through the veneer.

 

[jayrod12]

I would make the deck free standing vertically, and provide only lateral restraint bolts through the veneer. much easier to detail and more confidence in performance.

 

[msquared48]

That was my thought too, especially with the stone topping. Client will probably not want the columns at the outside wall though.

Mike McCann, PE, SE (WA)

 

[grogannc]

Freestanding is what has been proposed and the Owner really really doesn't want that. But granted, I'm sure they wouldn't like cracked veneer either.

 

[jayrod12]

Is it a main floor deck? Why the reservations on free standing? My alternative would be to remove a horizontal strip of veneer to fasten a ledger directly to the wood back up wall. But that will be difficult to accomplish.

 

[grogannc]

There is a basement level so there will be a porch below the deck. And they don't want to look at the columns apparently. I guess one solution would be to span the full length of the deck so you only have corner columns where it ties into the house.

 

[boo1]

The building code stipulates that nothing shall be supported by, or attached to, a brick or stone veneer. If you do want to attach to a veneered house by transferring the load from the ledger board through the veneer to the band board. But how do you know if the home's band board is made of plywood, a manufactured wood I-joist or a manufactured band board less than 1inch thick? How do you through bolt it (lags with the 4.5" space scare me)? How do you flash and seal the penetrations?

 

[grogannc]

like i say-its allowed in our code. not that I would do it in this case. but yeah you have to remove drywall inside to install the thru-bolts and it has to be flashed.

 

[HouseBoy]

I have NEVER seen a building CODE that allows a deck ledger to be attached to and supported by the brick veneer.
The IRC prescriptive code is very explicit about it too.
I HAVE seen building OFFICIALS who publicly state that they disregard that provision of the code.
In my experience, that is a terrible idea (to disregard that provision).

Regarding the OP... It looks to me that the "blocks" are to be strategically placed instead of the brick veneer at those 24" spaces and matings either 2x10 or 2x12 framing height (9" or 11"). Basically they act as "stand-offs" and the ledger is then able to hover out in front of the brick and spans the 24" between stand-off blocks.

Many provisions like this are not realistic and do not genuinely take into account the real conditions in the field. Too many problems come to mind to list here but a few are :, alignment of the deck outside and the floor framing inside, flashing, support for the brick above a ledger, suitability of any lintels that might exist below the proposed ledger, strength of any brick veneer "columns" below... to name a few.

Gravity forces along with horizontal forces in TWO DIRECTIONS should be considered for all.

 

[hawkaz]

What code is this chart from?

 

[grogannc]

NC 2012 Residential Building code