Brick veneer support for multi-story buildings 1

[archeng59]

I am working on a four story project with brick veneer full height of the building. I asked the architect where he wants to support the veneer at the upper floor levels because the total height exceeds 30 ft. We can do it at every floor level or every other floor level. He says it's my decision where to put the support angles because it's a structural issue. In part, he's correct since I design the framing supporting the veneer load, but the veneer is an architectural component & not a structural one. I believe it's his responsibility to determine control/expansion joint locations for the veneer just as he would for joints in any other siding material. Just curious about other's opinions.

 

[jayrod12]

I agree with both of you.

If it's up to you structurally, as he says, then I'd be putting them at every level. But that's just so the support at each level isn't working as hard.

What's the backup building constructed of?

 

[archeng59]

It's a structural steel system. It's my intent to support at every floor level & design the framing accordingly for gravity and lateral. But, I did this approach on a previous project where a different architect didn't want the joints at every floor level. So, I tried to avoid an argument about that and started a different argument.

 

[phamENG]

Yes, it is up to the architect. The architect made a decision: delegate the decision to the structural engineer.

That's fine - design it as efficiently as possible and move on. BUT...make sure you document that conversation/decision so, when the architect realizes there's going to be a significant horizontal joint with a "color matched" sealant larger than surrounding bed joints and hates it, you can get an extra service fee for changing it.

 

[jayrod12]

Makes sense re: past experience with architect's. I would've done the same, i.e. asked the question to the architect. But his response seems to indicate he doesn't care if there's a control joint at each floor, therefore each floor it is for simplicity.

 

[XR250]

Can you just support the upper level? Seems better than carrying the whole mess on a wood (i am asssuming) framed building.
edit - just saw it was a structural steel building.

 

[MotorCity]

Where to support the brick is more of a serviceability issue rather than a strength issue. A beam or foundation can be designed to support any height of brick. The movement of brick needs to match the relative movement of the building envelope, otherwise bad things happen (cracking brick or glass, water intrusion, etc.). The movement due to material shrinkage/expansion as well as vertical and horizontal movement of the building needs to be considered. I disagree that this decision can be made by only the architect or engineer. Input and consensus is needed from both people (and, ideally the contractor should have input).

 

[phamENG]

MotorCity - I always thought there was a fire safety element to it as well. If there's a fire and the backup wall goes, we don't a 50' panel of brick falling away from the building as a giant sheet. That and just general decay of brick ties. Most buildings (houses, anyway) over 30 years old just don't have them anymore.

 

[archeng59]

phamENG & jayrod12, it's likely this architect hasn't looked into it enough to realize there could be a joint at each floor and how it affects the aesthetics. But I have already mentioned it.

 

[archeng59]

XR250, I could support the veneer only at the 3rd floor level. But the beams will likely be rather large (deep and wide, i.e. flange width). This architect likes to use steel tube columns and center the grids in the stud wall so he doesn't have to furr out around any columns. It creates a challenge to use beams with a 6" or narrower flange width and columns 6x6 or smaller. Now that brick veneer support is in the mix, it's a bit more of a challenge. But, if it was easy, little kids could do it...

 

[JLNJ]

How big are the windows? Maybe you create supports at the level of the window head. Need lintels there anyway.

 

[archeng59]

JLNJ, that's an option. I need to work it out with the architect exactly where the ledge will be located. Somewhere near each floor level

 

[phamENG]

Windows is always problematic - you end up having to add a beam in the wall at the window head. Bracing becomes an issue.

 

[dik]

CFS? You can put them at ea second floor, and leave a bit of a gap beneath the shelf angle. About 40 years back, they replaced the brick veneer on a 20 +/-storey concrete building in Winnipeg. There was no gap and the brick veneer bowed and started 'falling off'. It was a design error. For CFS studs, I often use a deflection of L/720, not to compromise the brickwork. Building problem aggravated because conc shrinks over time and clay brick expands.

It's actually architectural stuff, and by doing it, you take ownership of it.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[XR250]

Most jobs I see have the brick supported on a shelf angle welded to the slab edge angle.

 

[dik]

xr250... and clips at 4' with a space for heat transfer. Make sure, if cold climate the shelf angles don't get too long for thermal expansion.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[milkshakelake]

@XR250 I always felt weird about that. I could attach a relieving angle to the pour stop, but I'm not sure how strong it would be. I'd probably weld some rebar into it as well to connect it to the slab. I've always connected it to the structural steel beams themselves because I'm sure those are strong.

 

[MotorCity]

Shelf angles can work but they should have vertically slotted holes to allow for adjustability. You don't know with any degree of certainty whether the angle will coincide with a mortar joint. Another issue that arises from this is who adjusts the angles? The mason? the steel erector? Architects hate them because of the thermal bridge they can create via the anchors attaching them to the superstructure. (I question this concern by reasoning how much energy is actually being lost through a 1/2" diameter anchor, but thats just me).

 

[dik]

This detail is often used, or variants of it. The support angle often has the leg up. The clip angles are generally half as long and spacing varies from 30" to 48", generally.

My notes give information about welding of HDG stuff and repair.

-IF WELDING OF HDG STEEL IS REQUIRED, REMOVE ALL GALVANIZING FROM AREAS TO BE WELDED TO PROVIDE 1" MIN BASE METAL AROUND ALL WELDS. WORK SHALL BE DONE IN ACCORD WITH AWS RECOMMENDATION WZC. PROVIDE VENTILATION AS REQUIRED. CLEAN FINISHED WELD AND TOUCH UP WITH TWO COATS OF ZINC RICH PRIMER. PRIMER SHALL OVERLAP EXIST GALVANISING BY 1/2" MIN.

Having an angle continuously in contact with a concrete wall or gradebeam does result in heat loss. Heat readily flows from the 'hot' gradebeam' the the excellent conducting metal angle.

I generally limit the length of the shelf angle to 20' or so due to thermal expansion (It's cool in Winnipeg in January). With a clip support at the ends of the Ls, I don't worry about the 1/4" gap I spec, and I really don't care where it falls on the mortar joint or brick.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik