Designing buildings and dealing with construction has always been a satisfying career for me. It is challenging to design a complete structural system, coordinate with the other consultants and create a clear set of construction documents for the contractor. Throughout my career, I’ve occasionally had a few panicked “Uh oh!” moments. I hope I’m not alone in admitting those happen. These typically occur far away from work when something prompts me to think about a project. I might see concrete being placed, then question whether I remembered to change the reinforcing callout on a mat slab I had just designed. I can’t stop thinking about it until I get back in the office to check.
I had an “Uh oh!” moment a few days after I started work at Simpson Strong-Tie. We have a training plan I call Catalog 101 where new engineers meet with each engineer who is an expert for a given product line. After I had met with our experts on holdowns, concrete anchors and engineered wood products, it was on to top-flange hangers (and my “Uh oh!” moment).
After learning a lot of things I didn’t know about hangers, we moved on to available options for some of our top-flange hangers – sloped, skewed, sloped and skewed, sloped top-flange, and offset top-flange. I learned that some hanger options get full load, some have small reductions and others large reductions. For example, the GLT with an offset top-flange gets 50% of the table load.
“Uh oh!”
I had recently designed a project and specified a bunch of GLT hangers with offset top-flanges. I hadn’t noticed there was a reduction for this modification; I just thought it was really cool that Simpson Strong-Tie had a hanger that worked at the end of a beam. Minor panic set in until I could check my calculations. Fortunately, the beams at the framing conditions that required offset hangers had half the load of the typical beams, so the hanger was okay even with the load reduction.
The Wood Construction Connectors Catalog has a Hanger Options Matrix that makes it relatively simple to see which options – sloped, skewed, concealed, welded – are available for each hanger. The pages following the options matrix have more detailed information about size restrictions and load reductions associated with each option. It can be somewhat tedious to sift through all of the options and apply the reduction factors, so I always recommend using the Simpson Strong-Tie Connector Selector® software to do the work for you.
Connector Selector software allows you to input you geometry and loads and returns a list of connectors that meet those requirements, including any reductions due to modifications. Connector Selector is a desktop application, which needs to be downloaded and installed on your PC. Engineers have indicated they like the functionality of Connector Selector, but wished the input was more intuitive and preferred it as a web application.
I’m happy to say we listen, and the new Simpson Strong-Tie Joist Hanger Selector web app is available now. The easy-to-use interface enables users to quickly select the connection details and print out results. You can access the app from any web browser without having to download or install special software. The allowable loads are automatically calculated to reflect reductions associated with modifications – no more “Uh oh!” moments for me (at least with hangers).
Give the new Joist Hanger Selector web app a try and let us know what you think. We always appreciate your feedback!