ReEngineering the Engineer: Get the Whole Job Done Right the First Time
Modeling and design software has made our design life really simple these days. The ability to add or modify loads and reconfigure framing provides a lot of flexibility in determining the best system for floors and lateral systems. However, at the end of the day, someone still has to be able to build it.
BIM software has made it easy to convert 3D models into a bunch of framing plans on sheets of paper, and you can make a lot of sheets in a hurry. But that’s only part of our job. We’re still required to get the project over the finish line, at least for our engineering element. That means making sure the construction side of the equation can accurately interpret our design intent.
Proper Preparation
As the adage goes, the best preparation for tomorrow is to do today’s work exceedingly well. Producing a poorly thought out set of drawings can cost you dearly during construction administration and impact your profitability. The onslaught of RFIs can be a killer if you haven’t done your homework. Rest assured, they will all come at the worst time and have the highest priority, because construction has already started and there are deadlines to meet.
Although our main task seems to be getting beam sizes and column locations on the drawings, the trade partners need to know exactly how things go together. And if you think they’re going to figure it out for you, you have another thing coming. Early in my career, the shop drawings we received from fabricators were prepared by folks who had been in the industry for a while—perhaps had been in the field. They understood how things go together and took a stab at what you meant. Those days are long gone.
If it’s not on the drawings, you’re getting an RFI. There isn’t going to be an educated guess. And if the missing information is important enough, you might need to explain a change order to your client. That rarely ends well. So how can we be well prepared for tomorrow?
Look at the Load Path
For our young engineers, I find it helpful to get them to think about the load path. If they’re modeling accurately, many issues will be visible in the model especially if you’re willing to dig a little and know where to look. Member sizes and locations are important, but being able to transfer loads from one member to the next is critical. What looks good on paper may not work at all.
You could have several members coming together at a joint, but some of them may be at different elevations or skewed or sloped. Drawing different sections of that joint—to scale—helps you visualize connectivity problems.
Your framing scheme may require members under members to simplify erection or fabrication costs. That’s generally not a problem when the dropped members frame directly into columns, but sometimes they need to frame into other beams. That may not leave much meat for a connection.
There may be several different ways to get the members attached, some messier than others. Sometimes the connection gets too complicated. If each new solution creates another equally complicated problem, you’re probably barking up the wrong tree. Learning when and how to take a step back out of the rabbit hole is an important skill. There have been numerous times where I’m struggling with a connection, and the best answer is to reframe that area to make the problem go away. That’s not always possible, but certainly an option worth looking at.
Once you have the problem solved, get the detail drawn! It’s not a secret. You’ve figured it out, so let the person who has to detail it know your design intent, which saves everyone time. The detailer gets to detail it correctly the first time, and you don’t have to answer an RFI before or during shop-drawing review.
It’s in the Details
So why is any of this important? As I noted earlier, you aren’t going to get any help finishing your job. You ultimately have to answer the detail questions to get shop drawings completed anyway. And I can attest from personal experience, doing a good job detailing while you’re designing is way more efficient than trying to do it a couple months later after you’ve moved on to something else, waiting for the RFIs and shop drawings to arrive.
Depending on how messy the project is, getting your head back into the details of what you meant in the first place takes time you probably don’t have, and that works against project profitability. Both of those issues are important, especially when being efficient with your time and project profitability likely are (at least) two of the metrics used in your performance review. Take the time to finish the job the first time through; it’s the better solution all around.
About Douglas Fitzpatrick
Douglas G. Fitzpatrick, P.E., is the founder, president and practicing engineer of Fitzpatrick Engineering Group, a 14-year-old structural engineering firm specializing in commercial and healthcare building design.
