Author: Paul McEntee

A couple of years back we hosted a “Take your daughter or son to work day,” which was a great opportunity for our children to find out what their parents did. We had different activities for the kids to learn about careers and the importance of education in opening up career opportunities. People often ask me what I do for Simpson Strong-Tie and I sometimes laugh about how my son Ryan responded to a questionnaire he filled out that day: Q. What is your mom/dad's job? A. Goes and gets coffee and sits at his desk Q. What does your mom/dad actually do at work? A. Walks in the test lab and checks things When I am not checking things in the lab or sitting at my desk drinking coffee, I manage Engineering Research and Development for Simpson Strong-Tie, focusing on new product development for connectors and lateral systems. I graduated from the University of California at Berkeley and I am a licensed Civil and Structural Engineer in California. Prior to joining Simpson Strong-Tie, I worked for 10 years as a consulting structural engineer designing commercial, industrial, multi-family, mixed-use and retail projects. I was fortunate in those years to work at a great engineering firm that did a lot of everything. This allowed me to gain experience designing with wood, structural steel, concrete, concrete block and cold-formed steel as well as working on many seismic retrofits of historic unreinforced masonry buildings.

How to Safely Select Nail Substitutions for Connectors

A few days ago, I was speaking to a customer about an application using nail substitutions for a joist hanger installation. Her questions come up often, so I thought I would dedicate a blog post to some of the resources available that cover the use of different nails in connectors.

Designers and builders often wish to use different fasteners than the catalog specifies. The application could require short nails that don’t penetrate through the back of a ledger or they want to use screws or sinker nails for easier installation. The Wood Connectors Catalog provides multiple options for alternate nailing for face mount hangers and straight straps on page 27.

The load adjustments for alternate fasteners cover substitutions from a common diameter of 16d to a 10d, or a 10d to an 8d. Multiple different replacement lengths are also covered, with reduction factors ranging from 0.64 to 1.0.

It is important to remember that double shear hangers require 3” minimum joist nails. Short nails installed at an angle in double shear hangers will not have adequate penetration into the header.

Fastener - Double Shear — Fastener – Double Shear

Pneumatic nail guns used for connector installation are commonly referred to as positive placement nail guns. These tools either have a nose piece that locates connector hole, or the nail itself protrudes from the tool so that the installer can line the nail up with the hole. Most positive placement tools do not accept nails longer than 2½”, so framers using these tools will want to use 1½” or 2½” nails. To accommodate installers using pneumatic nails, we have a technical bulletin T-PNUEMATIC. This bulletin provides adjustment factors for many of our most common embedded holdowns, post caps and bases, hangers and twist straps.

The question of nail size also comes up when attaching hangers to rim board, which can range from 1” to 1¾”. The adjustment factors in C-2013 don’t necessarily apply with rim board, since the material may be thinner the length of the nails used. We also have a technical bulletin for that application – T-RIMBDHGR.

Several of the reduction factors are the same as those in the catalog. Testing of hangers with 10dx1½ nails on 1” OSB or 1¼” LVL did not do as well, however. We observed that once the nails withdrew a little bit under load, they quickly lost capacity. For that reason, we recommend full length 10d or 16d nails on those materials.

Understanding that alternate fasteners are available for many connectors can help you pick the right fastener for you application. When you specify a connector, it is important to also specify the fasteners you require to achieve your design load.

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Know Your Code

I attended a CFSEI and Steel Framing Alliance webinar last week entitled Specifying Cold-Formed Steel: Finding and Avoiding Pitfalls in Structural General Notes and Architectural Specifications. The presenter was Don Allen, P.E., from DSi Engineering, LLC, and he focused on issues specifically related to design and specification of cold-formed steel (CFS) in contract documents.

Happy Thanksgiving!

Wishing you and your loved ones a Happy Thanksgiving. Our U.S. offices are closed Thursday and Friday, November 28-29 for the holiday. Talk to you next week!

– Paul

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Simpson Strong-Tie Literature at Your Fingertips

A couple of years ago, my brother-in-law asked if I could stop by the swim club where he is a board member. He was overseeing a construction project to upgrade the buildings and patio covers, which involved dry-rot repairs and the addition of Simpson Strong-Tie® connectors to create a continuous load path. He wanted me to meet with the contractor and make some suggestions for alternate connectors. The as-built conditions didn’t work for the specified connectors at a few locations, and there were some spots where he thought the connectors were “ugly.” I’m probably in the minority on this, but I think shiny galvanized steel connectors are just beautiful. So the “ugly” comment stung a little bit.

Once I got over my hurt feelings, I grabbed my Wood Construction Connectors catalog, a Deck Connection and Fastening Guide, and a few other fliers and technical bulletins that I thought might be helpful and drove across town to meet them. With literature in hand, we were able to come up with ways to work around the more difficult areas, and also select some more aesthetically pleasing architectural connectors at prominent locations. I thought we were done, and then the contractor had a few more questions on anchoring that I needed an Anchoring and Fastening Systems Catalog to look up some information on – and I didn’t have one! I managed to muddle through with my smartphone and find the information online, but couldn’t help but think that there had to be a better way to access design information when you are out of the office.

The better way has arrived in the latest version of the Simpson Strong-Tie® Literature Library mobile app. It was just launched this month and is much more comprehensive than the first version. There are several new features that I wanted to highlight for you.

Steel Roof Decking

My wife, Kristin, sometimes gets angry with me while grocery shopping. It’s understandable. She’s asked me to grab some tomatoes or a loaf of bread and instead I’m just standing there looking up at the ceiling. Technically, it’s not a ceiling, but the underside of the roof, and I’m looking up to see the connection detailing, including whether or not the steel roof deck I’m looking at was welded, pinned, or screwed down to the steel joist, beam and angle supports.

If you’re a structural engineer, you might also do this inside your local supermarket, Target, Walmart or The Home Depot. Many of these “big box” stores are typically constructed of tilt-up concrete perimeter walls, tube steel interior columns, and roofs built of steel joists, girders and decking. Though Simpson Strong-Tie is well known in the light-frame wood construction industry, some may not know that we’ve long been developing and selling anchors and fasteners for commercial construction.

Outside of a few dips into a Verco or ASC steel decking catalog from my consulting days in Las Vegas, my first real foray into the steel decking industry was about two years ago. I was asked to assist in representing Simpson Strong-Tie as an associate member at the Steel Deck Institute’s (SDI) quarterly meeting held just down the road in Dallas in November 2011. Since joining SDI, my main focus has been to find out what the industry needs, both from the installer’s and designer’s standpoint for steel deck attachment. Though we’ve had a screw attachment offering for years, my colleagues and I have worked to develop a better overall system which now includes:

City of San Francisco Implements Soft-Story Retrofit Ordinance

The city of San Francisco is a unique construction environment that is 98% built-out with little new residential construction. Protecting the existing structures is particularly imperative to save the character of the city and maintain the population base by preventing a major migration out of the city after a large seismic event.

The Community Action Plan for Seismic Safety (CAPSS) was a San Francisco Department of Building Inspection 10-year-long study started in 1998 to study earthquake risks in San Francisco and develop suggestions for mitigating loss of life and property damage from future earthquakes. I once worked as a volunteer on a sidewalk survey to inventory soft-story buildings as part of CAPSS. The key recommendations of CAPSS evolved into the CAPSS Earthquake Safety Implementation Program (ESIP), which has 50 tasks that will be implemented over the next 30 years.

One of those tasks includes the Mandatory Soft-Story Retrofit Program, which Mayor Ed Lee signed into law on April 18, 2013 at the annual commemoration of the 1906 San Francisco Earthquake. The law requires wood-framed buildings that:

Were built prior to 1978
Are three stories or more and,
Have five or more dwelling units

to be evaluated and brought into compliance. The city sent notices to building owners on September 15. It’s estimated that there are between 4,000 and 10,000 structures that fall under the program.

Getting Involved and Staying Connected in the Industry

I’m excited to share some tips on getting more involved with the structural engineering community. There are many organizations and industry associations related to structural engineering that it can feel daunting to try to meet all of the key players and make a name for yourself.

I have a really unique and fun job at Simpson Strong-Tie as a field engineer for our light-frame construction products, which include connectors, fasteners, and lateral systems. As a field engineer, I spend most of my time out on the road visiting engineers, architects, building officials, contractors, and others who need technical assistance using our product lines. While this means I spend a good chunk of time in SoCal traffic, I do get to talk to lots of different people working on projects ranging from small home remodels that might be using our new Strong-Frame® special moment frame to huge multi-family housing projects with several thousand units.

I also make sure to attend as many industry association functions as I can, because these are the best places to network and meet other professionals. There are many great organizations, including the Structural Engineers Association, which has chapters all over the United States. The California chapters have very strong participation. I also suggest getting involved in other industry organizations that include people outside of the profession, such as building officials, inspectors, contractors, builders, and architects. These people play an integral part in the construction industry and it’s important to understand their role and importance in supporting structural engineering.

Not Just A Connector Company

I write a lot about testing on this blog, from my first post about testing to the series I did on how we test different products (hangers, holdowns, fasteners). This week I’d like to highlight some unique testing we’ve been doing to support one of our new product lines. Simpson Strong-Tie® recently introduced our Repair, Protection and Strengthening Systems for Concrete and Masonry. The new product line is the result of our acquisition of Fox Industries, Inc. in 2011.

In the past, I’ve shared some of the more fun tests we’ve run, like the bowling ball test or 40 kip hangers. This week we’ll take a sneak peek at testing of the FX-70® Structural Repair and Protection System. FX-70 uses high-strength fiberglass jackets and high-strength water-insensitive grouting materials to repair and protect wood, steel, and concrete structural members. The system is primarily used on piles in marine environments.

Fx-70 installation on wood piles. Image credit: Simpson Strong-Tie.

Mixing It Up with Concrete Specification

Around Christmas, the Engineering Department does a white elephant gift exchange. We have no idea who framed this picture and wrapped it up the first time.

Several of our lab technicians (plus a product manager) are posing for the camera, and obviously trying to flex while sucking their bellies in during a concrete pour to test our SSTB(R) anchors. The tradition has it that if you end up with this picture, you hang it on your wall and re-gift it at next year’s gift exchange – so there it is, on the wall in Engineer Dustin’s office. The trick has become wrapping it so that nobody recognizes that it is the picture frame.

Speaking of concrete, between our test labs in Addison, Ill., Stockton and Pleasanton, Calif., we test a lot of concrete. We will certainly be doing a lot more testing to continue to support our new Repair, Protection and Strengthening Systems for Concrete and Masonry product line. But I will ask the lab technicians to keep their shirts on.

TED Talk – Michael Green: Why We Should Build Wooden Skyscrapers

I have been following TED Talks for a few years now. Like most websites I have on my “to visit” list, I couldn’t tell you how I found them. It may have been a link on some other website, or a friend on Facebook, or maybe linked on another blog somewhere. What is TED? I’ll steal from their website:

TED is a nonprofit devoted to Ideas Worth Spreading. It started out in 1984 as a conference bringing together people from three worlds: Technology, Entertainment, Design. Since then its scope has become ever broader. Along with two annual conferences — the TED Conference and TEDGlobal — TED includes the award-winning TED Talks video site, the Open Translation Project and TED Conversations, the inspiring TED Fellows and TEDx programs, and the annual TED Prize.

New content is posted on TED every day, so I often miss cool stuff. Thanks to one of our Canadian engineers for pointing out a talk by architect Michael Green, who makes a case for why we should build wooden skyscrapers. I did a previous post about the Timber Tower Research Project that Skidmore, Owings & Merrill LLP did for a 42-story wood framed building. Mr. Green makes the case for taller wood structures from an environmental standpoint and carbon dioxide output of concrete and steel versus wood.

The 12 minute video is worth a listen. The TED Blog post is here: Why tall wooden buildings must be our future: a visual essay by Michael Green.

– Paul

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