Continue to Site

Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations 3DDave on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Coordination of Masonry Joints - SE's or Archs?

Status
Not open for further replies.

JAE

Structural
Jun 27, 2000
15,639
Just a question I'd like to put out there -

For brick masonry or
for concrete block masonry:

What is your area's or industries standard operating proceedure for calling out the location, spacing, and details of masonry joints?

Does the structural engineer deal with them?
Does the architect?
Do each think the other is specifying them and they get missed?
Do both coordinate together and they get shown/specified somehow?
Does the engineer recommend a spacing and the architect show them?
etc.

Just wondering - I can't seem to find anything on the BIA, NCMA, other masonry websites as far as who is responsible (similar to AISC's code of standard practice where they indicate who does what).

Thanks

 
Replies continue below

Recommended for you

In our practice, the Structural Engineer locates and details the joints. Don't know what other firms do.
 
JAE...to me this is one of those issues that the SE takes the lead. In most instances, we allow the architect to aesthetically "design" features, then we make them work structurally.

Architects hate joints of any kind...especially those that they must put in and over which they have no aesthetic control. Given that, we often have to "force" the issue and require their inclusion.
 
Agree with Ron here.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
 
Engineer locates them, usually with some negotiation. Architect shows their location on drawings. Engineer should detail joints in bearing walls, architect in veneer.
 
In my practice I show the location of either and MCJ#1 or and MCJ#2 on the foundation plans. An MCJ#1 is for a typical vertical cj. The MCJ#2 is for and control joint that starts under the lintel and then goes up the wall. I then have a detail that shows these two types of configurations. To help control cracking I place bond beams at the same levels as the precast lintels and at the bottom of window sill elevation.

I usually have the architect show the control joints on their elevations as well because this effects how stucco control joints might be located.

For brick veneer I usually just specify every 25 feet and be done with it. I haven't done any fancy brick veneer work so this is usually not a big deal. Again have the architect show this on the elevations as well.

Too many times I've seen people just spec these in the specifications and they either get completely missed or they get installed wrong. Often you'll end up with too many, too few, 8" columns adjacent to doors or windows because they didn't use the right style, etc...

John Southard, M.S., P.E.
 
I generally locate them and send them on to the Architect for review.

Dik
 
I work for an AE firm, typically I tell the architect to locate them on their elevations if they are concerned where they are located for aesthetics (and give them maximum spacing requirements); otherwise, I will provide a general note for maximum joint spacing.
 
I agree that for the veneer the architect needs to provide the locations and details.

If you have load bearing reinforced CMU and structure which is working hard (especially highly stresses shear walls) the EOR needs to think the jointing through (and show it on his drawings), or he won't get a structure which acts as he planned. If the SE doesn't show the joints then he ought to be prepared to have a joint just about anywhere. For some buildings "anywhere" is OK but for many it is not.

Quite a few people I run in to think control joints in the veneer and CMU backup need to "line up". They don't know that the joints serve two different purposes (one for swelling and one for shrinkage).
 
These are good comments - keep them coming.

Full disclosure: I'm sitting on a panel at a seminar for masonry and this is the topic I'm to speak on.

Some of you above have hinted at a coordination that is required between you and the architect.

This is particularly what I'm interested in.

My practice has been to communicate to the architect the required spacing and then they would show it on their elevations (like the comments above).

In one case the architect prompted me to review where he had put joints - vs. me initiating the conversation. The elevations seem to be the best place for brick veneer. For CMU though I would think the structural plans would be better....thoughts?

So what is the ideal process for ensuring that the joints get on the plans? Step by step what should happen?
 
In my experience it a regional difference depending on past failures of wall systems. Most work in Michigan where brick veneer is popular the architects are pretty good about showing wall joints in elevation and detailing them.

When working in Florida the architects usual response is either "what's a wall joint?" or "you mean stucco joint." And the stucco joints are usually only in the stucco not thru the masonry wall.
 
Being in-house at an A/E firm, the architectural designer would show them on the building elevations with our input. Joints that would often get missed or overlooked would be joints on long interior masonry walls, drywall, etc. Low height masonry walls would need closer joint spacing. I also insist that a joint be placed in the masonry at a change in footing type.

For multi-story brick veneer, we would collaborate with the architectural people on location of shelf angles and soft joints.

We had standard details that I developed for our typical masonry joints.

I also have a "catch-all note" (as a backup) that describes all the above.
 
I like to detail them in both the veneer and the CMU backup after the Arch has incorporated the ones I've shown and possibly suggested other locations. I provide the Arch with standard details for his use.

Many Arch are pretty/very good in locating joints and a few need the application of a 2x4 to the left side of their hatrack.

It's a brittle material and subject to differential movement if using brick and CMU matl. The Arch can either locate the 'cracks' or live with where they will occur.

Dik
 
jike, what's your "catch-all" note? Can you share it?
 
In Spain the architect is as well the structural designer so he or she places them in all kind of plans. For the cases where an engineer or consulting firm cares of the structure, coordination appears.
 
JAE:

I am in the process of moving, so everything right now is packed away in boxes. I will dig out the note next week.....
 
For load bearing CMU, I specify joint locations. Not for veneer.
 
In my experience, the person who calls the material calls the joints, that has generally broken down according to whether it is a strength material or a beauty material, masonry being structural, brick veneer being architectural.

Michael.
Timing has a lot to do with the outcome of a rain dance.
 
Another key point is that if you're counting on arching action in the lintel design, there cannot be a joint on either side of the opening. If a joint is designed there, or it is unknown, you need to design the lintel for the whole rectangular load above the opening.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor