Jerry Painter
Most mason contractor safety programs require some training, but the joke is how often you must retrain. Whenever you ask a contractor that question, you will get a multitude of answers. They include: once at hire, whenever it appears their employees have forgotten their training, every month, every week and every day. Yes, I know some contractors will be facetious with their opinions, but there is some truth in all of that.
I had a kindergarten teacher tell me once that she and I were in the same type of business. It seems that sometimes both of us would have to start over every day. Have you ever had a mason show up for work right on time or a little late and want to distract you with some conversation?
That is the way I feel when I get calls about how or why masonry is done a certain way. I’ve received several calls lately regarding anchoring veneers to structures. So, let’s convene the training class and review the material necessary.
There will be a test. Not with this column, but every day on the jobsite. Will all contractors that have the TMS 402/602-16 available for your employees please raise your hand? Now, all building officials that have the Building Code Requirements and Specification for Masonry Structures available in your department, raise your hand.
Wait a minute now. How can you review plans and inspect masonry structures without the Code? It is not reprinted in the IBC, FBC, or the project plans. It is included by reference and is still considered the law. Architects and engineers, please raise your hand if you have the TMS 402/602 in your office? Ok, let’s get to the point.
Anchoring masonry veneers are prescribed in TMS 402-16. If anyone is using an edition earlier than 2013, you are seriously out of date. Grab your book or pull up the Code and turn to TMS 402 Part 4, Prescriptive Design Methods.
You should then find Chapter 4 Veneers. Section 12.2 is the section on Anchored veneer. Within this section, you will find 12.2.2, which is the section on Prescriptive requirements for anchored veneer. Section 12.2.2.5 should be read with serious comprehension as it covers Anchor requirements.
Now we get to the heart of our retraining. Section 12.2.2.6 covers masonry veneer anchored to wood backing. Here are the requirements for nail size and location, corrosion resistance, and distance of the veneer from the wood backing. You’ll see that there is a 1” maximum distance for using a corrugated sheet metal wall tie, and a 1” minimum distance for the airspace between the back of the veneer and wood backing.
I have personal knowledge that plain galvanized wall ties show considerable rust in seven years and are completely deteriorated in 25-30 years. Masonry is forever, so why are we cutting its performance to just a few years?
Section 12.2.2.7- Masonry veneer anchored to steel backing gives us the requirement of adjustable anchors, the type of screws, and distance from the backing.
Section 12.2.2.8- Masonry veneer anchored to concrete backing also requires adjustable anchors.
Section 12.2.2.9- Masonry veneer anchored to masonry backing does not allow the use of wall ties. It allows wire ties, adjustable anchors, or joint reinforcement. That bears repeating for clarity. Corrugated or scalloped wall ties are not allowed to anchor a masonry veneer to a masonry backup.
The use of hot-dipped galvanized coatings should be considered a minimum. Remember that if you bend the anchor, the coating can be cracked, which allows for rust to form. I have a 3/16” mill galvanized wire anchor that rusted through in a conical fashion in 40 years. Please get it right the first time, because the next time it will be very expensive. Remember, you are being tested every day.
All this class and training talk reminds me of a children’s song from long ago. When we all work together, together, together when we all work together how happy we’ll be.
RAISE THE LINE and come on around the corner.