Brick Veneer for Guardrail Support

[JDV22]

Hey everyone!

I have a customer who wants to support a guardrail with brick veneer. The reasoning is that the brick is already installed and removing the brick to attach to the wall behind is not cost effective at this point in the project. See below for a very rough sketch that is not to scale:

I have always been under the impression that you could not attach directly to brick veneer for any significant loading (i.e. decks). One of the guys in the office said that you can count on brick veneer for lateral stability (not seismic or wind resistance, but traction), but never gravity loads. He said for a guard under this load scenario, I could use the brick veneer. Hilti has some options and load values for sleeve anchors into hollow masonry, so I can work through a design, but I'd like to be able to back up my choice to attach to brick veneer with some sort of code reference. So far, I have not seen any.. Have any of you encountered this type of connection and do you have any thoughts on the ability brick veneer to resist a 200lbf load imparted from the guardrail onto the wall?

Thanks in advance!

 

[XR250]

I'd be OK with it as long as you are too close to the edge of the wall. You would likely want to use screened epoxy anchors.
You probably only need one anchor near the top of the post.

 

[JDV22]

@XR250

Thanks for the response! What is driving your decision? I am a young engineer - so I would say that I do not qualify for "Engineering judgement" yet.. Have you just seen them work in your experience or does it not concern you since it is not under constant loading? is it a probability of failure deal? I'm not trying to be a bother - I just like to dig in when I can so I can better understand.

Thanks!

 

[jayrod12]

I believe XR meant to say ".... as long as you aren't to close to the end of the wall"

Some of it is engineering judgement. But think about the fact that there are building all over the world that are only made of brick. Therefore there is some capacity there. For the situation you have shown, you're looking at a maximum of what 250 lbs? Seems like a pretty minor amount of load. therefore a full thickness veneer in good condition should be able to resist that provided there aren't extenuating circumstances like a control joint or an end of wall nearby to influence the capacity.

 

[dreber]

Yea, a guardrail needs to be designed for a 200 lb unfactored point load (or 50 plf, whichever greater).

So, all you are relying on the brick for is to resist 200 lb.

The contractor will likely prefer that you use screw anchors, such as HILTI HUS-EZ.

You can design the connection using ESR 3056.

As said before, watch the edge distance between the anchor and the nearest face of the brick wall.

Page 5 of the ESR has a minimum 4" edge distance for a 3/8"Φ screw anchor:

https://www.buildsite.com/pdf/hilti/KWIK-HUS-EZ-KH-EZ-Hex-Head-ICC-ES-Evaluation-2017854.pdf

=========================
David Reber

http://www.kadent-structures.com

 

[NorthCivil]

Things vary case by case, this may be kosher.

but heard a nice little nugget of wisdom from a colleague the other day when we were looking at something similar but different:

"its bad practice to screw something back to the cladding, rather than back to the building"

A brick veneer cladding may function theoretically for this purpose, but consider the global scenario, differential movements, etc

 

[bones206]

The contractor will likely prefer that you use screw anchors, such as HILTI HUS-EZ.

You can design the connection using ESR 3056.

Careful, this ESR is applicable to CMU, not brick.

 

[JDV22]

Thanks for all of the input!

The plan is going to be to size up a hilti sleeve anchor rated for hollow brick and outline any necessary geometry constraints!

 

[masonrygeek]

Sometimes we get hung up on terminology like "veneer". While brick veneer is not *meant* to take any additional loads, brick veneer *can* - it just makes you move away from some of the prescriptive requirements and do a more "engineered" design. So do your design with the sleeve anchor, but also consider differential movement and if the loading would affect the veneer ties.

 

[dik]

Sorry I missed this... Could you do something like:

or

cantilever the top rail over a foot or so? Your top rail will likely span a couple of feet, and no load to the wall... or connect to a metal plate at the top rail only; you might have a couple of fasteners. Running a vertical connection will not be very effective.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[JDV22]

@dik

We actually are planning on doing a cap plate for the top rail with just a couple of fasteners now. We still need to keep the vertical plate to attach our infill, but will not be attaching it to the wall the way it's shown in the sketch I provided earlier in the thread.

Adjusting the post spacing and cantilevering a foot or 18" past would have been a good solution also! I guess that's the nature of engineering - there are always several solutions to a given problem. Thanks for all the help everyone!