Tag: Simpson Strong-Tie

Meet the First Simpson Strong-Tie Engineering Excellence Fellow with Build Change

Introducing James P. Mwangi, Ph.D., P.E., S.E. – our first annual Simpson Strong-Tie Engineering Excellence Fellow with Build Change. James Mwangi will write a quarterly blog about his experience throughout the Fellowship.

I’m delighted to have been asked to contribute this post and feel honored to be the first-ever Simpson Strong-Tie Engineering Excellence Fellow with Build Change. It’s my hope that this post will inform you about my professional background, why I applied to the Fellowship and how I think the Fellowship can benefit people and the structures they live, work and go to school in.
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Top 10 Changes to Structural Requirements in the 2018 IBC

This blog post will continue our series on the final results of the 2016 ICC Group B Code Change Hearings, and will focus on 10 major approved changes, of a structural nature, to the International Building Code (IBC).

  1. Adoption of ASCE 7-16
    • The IBC wind speed maps and seismic design maps have been updated.
    • A new section has been added to Chapter 16 to address tsunami loads.
    • Table 1607.1 has been revised to change the deck and balcony Live Loads to 1.5 times that of the occupancy served.
  2. New and Updated Reference Standards
    • 2015 IBC Standard ACI 530/ASCE 5/TMS 402-13 will be TMS402-16.
    • ACI 530.1/ASCE 6/TMS 602-13 will be TMS 602-16.
    • AISC 341-10 and 360-10 have both been updated to 2016 editions.
    • AISI S100-12 was updated to the 2016 edition.
    • AISI S220-11 and S230-07 were updated to the 2015 edition.
    • AISI S200, S210, S211, S212 and S214 have been combined into a new single standard, AISI S240-15.
    • AISI S213 was split into the new S240 and AISI S400-15.
    • ASCE 41-13 was updated to the 2017 edition.
    • The ICC 300 and ICC 400 were both updated from 2012 editions to 2017 editions.
    • ANSI/NC1.0-10 and ANSI/RD1.0-10 were all updated to 2017 editions.
  3. Section 1607.14.2 Added for Structural Stability of Fire Walls
    • This new section takes the 5 psf from NFPA 221, so designers will have consistent guidance on how to design fire walls for stability without having to buy another standard.
  4. Modifications of the IBC Special Inspections Approved
    • Section 1704.2.5 on special inspection of fabricated items has been clarified and streamlined.
    • The Exception to 1705.1.1 on special inspection of wood shear walls, shear panels and diaphragms was clarified to say that special inspections are not required when the specified spacing of fasteners at panel edges is more than 4 inches on center.
    • The special inspection requirements for structural steel seismic force-resisting systems and structural steel elements in seismic force-resisting systems were clarified by adding exceptions so that systems or elements not designed in accordance with AISC 341 would not have to be inspected using the requirements of that standard.
  5. Changes Pertaining to Storm Shelters
    • A new Section 1604.11 states that “Loads and load combinations on storm shelters shall be determined in accordance with ICC 500.”
    • An exception was added stating that when a storm shelter is added to a building, “the risk category for the normal occupancy of the building shall apply unless the storm shelter is a designated emergency shelter in accordance with Table 1604.5.”
    • Further clarification in Table 1604.5 states that the type of shelters designated as risk category IV are “Designated emergency shelters including earthquake or community storm shelters for use during and immediately after an event.”
  6. Changes to the IBC Conventional Construction Requirements in Chapter 23
    • The section on anchorage of foundation plates and sills to concrete or masonry foundations reorganized the requirements by Seismic Design Category (SDC) and added a new section on anchoring in SDC E. It also states that the anchor bolt must be in the middle third of the width of the plate and adds language to the sections on higher SDCs saying that if alternate anchor straps are used, they need to be spaced to provide equivalent anchorage to the specified 1/2″- or 5/8″-diameter bolts.
    • The second change permits single-member 2-by headers, to allow more space for insulation in a wall. 
  7. Modification to the Requirements for Nails and Staples in the IBC
    • ASTM F1667 Supplement One was adopted that specifies the method for testing nails for bending-yield strength and identifies a required minimum average bending moment for staples used for framing and sheathing connections.
    • Stainless-steel nails are required to meet ASTM F1667 and use Type 302, 304, 305 or 316 stainless steel, as necessary to achieve the corrosion resistance assumed in the code.
    • Staples used with preservative-treated wood or fire-retardant-treated wood are required to be stainless steel.
    • The new RSRS-01 nail was incorporated into TABLE 2304.10.1, the Fastening Schedule. The RSRS nail is a new roof sheathing ring shank nail designed to achieve higher withdrawal resistances, in order to meet the new higher component and cladding uplift forces of ASCE 7-16.
  8. Truss-Related Code Change
    • The information required on the truss design drawings was changed from “Metal connector plate type” to “Joint connection type” in recognition that not all trusses use metal connector plates.
  9. Code Change to Section 2304.12.2.2
    • A code change clarifies in which cases posts or columns will not be required to consist of naturally durable or preservative-treated wood. This change makes the requirements closer to the earlier ones, while maintaining consistency with the subsequent section on supporting members.
    • If a post or column is not naturally durable or preservative-treated, it will have to be supported by concrete piers or metal pedestals projecting at least 1″ above the slab or deck, such as Simpson Strong-Tie post bases that have a one-inch standoff.
  10. Code Change to IBC Appendix M
    • A code change from FEMA makes IBC Appendix M specific to refuge structures for vertical evacuation from tsunami, and the tsunami hazard mapping and structural design guidelines of ASCE 7-16 would be used rather than those in FEMA P-646.

Once the 2018 IBC is published in the fall, interested parties will have only a few months to develop code changes that will result in the 2021 I-Codes. Similar to this last cycle, code changes will be divided into two groups, Group A and Group B, and Group A code changes are due January 8, 2018. The schedule for the next cycle is already posted here.

What changes would you like to see for the 2021 codes?

Keep Your Roof On

He huffed, and he puffed, and he blew the roof sheathing off! That’s not the way kids’ tale goes, but the dangers high winds pose to roof sheathing are very real. Once the roof sheathing is gone, the structure is open and its contents are exposed to the elements and much more vulnerable to wind or water damage. It is a storyline that we meet all too often in the news.

About two years ago, the ASTM subcommittee on Driven and Other Fasteners (F16.05), addressed fastening for roof sheathing in high-wind areas by adding a special nail to ASTM F1667-17 – Standard Specification for Driven Fasteners: Nails, Spikes and Staples. The Roof Sheathing Ring-Shank Nail was added to the standard as Table 46. Figure 1 illustrates the nail and lists its geometrical specifications. This is a family of five ring-shank nails that can be made from carbon steel or stainless steel (300 series). Specific features of these nails are the ring pitch (number of rings per inch), the ring diameter over the shank, the length of deformed shank and the head diameter. Also, note B specifies that the nails shall comply with the supplementary requirement of Table S1.1, which tabulates bending yield strength. In this diameter class, the minimum bending yield strength allowed is 100 ksi.

Figure 1. Roof Sheathing Ring-Shank Nails (ASTM. 2017. Standard Specification for Driven Fasteners: Nails, Spikes and Staples, F1667-17. ASTM International, West Conshohocken, PA.)

The IBHS (Insurance Institute for Business and Home Safety) discusses roof deck fastening in its Builders Guide that describes the “FORTIFIED for Safer Living” structures. The IBHS FORTIFIED program offers solutions that reduce building vulnerability to severe thunderstorms, hurricanes and tornadoes. Keeping the roof sheathing on the structure is critical to maintaining a safe enclosure and minimizing damage, and roof sheathing ring-shank nails can be part of the solution. As Figure 2 from IBHS (2008) shows, every wood-frame structure has wind vulnerability.

Figure 2. Hurricane, high wind and tornado regions of the US (IBHS. 2008. Builders Guide, Fortified for Safer Living. Tampa, FL. 81 pp.)

More importantly for the wood-frame engineering community, the Roof Sheathing Ring-Shank Nails are being included in the next revision of the AWC National Design Specification for Wood Construction (NDS-2018), which is a reference document to both the International Building Code and the International Residential Code. You will be able to use the same NDS-2018, chapter 12 withdrawal equation to calculate the withdrawal resistance for Roof Sheathing Ring-Shank Nails and Post Frame Ring-Shank nails. The calculated withdrawal will be based on the length of deformed shank embedded in the framing member. Also, Designers need to consider the risk of nail head pull-through when fastening roof sheathing with ring-shank nails. If the pull-through for roof sheathing ring-shank nails is not published, you will be able to use the new pull-through equation in the NDS-2018 to estimate that resistance.
Simpson Strong-Tie has some stainless-steel products that meet the requirements for Roof Sheathing Ring-Shank Nails. These will be especially important to those in coastal high-wind areas. Table 1 shows some of the Simpson Strong-Tie nails that can be used as roof sheathing ring-shank nails. These nails meet the geometry and bending yield strength requirements given in ASTM F1667. See the Fastening Systems catalog C-F-2017 for nails in Type 316 stainless steel that also comply with the standard.

Table 1. Simpson Strong-Tie collated nails made from Type 304 stainless steel that comply with F1667-17 specifications for Roof Sheathing Ring-Shank Nails.

Improve your disaster resilience and withstand extreme winds by fastening the sheathing with roof sheathing ring-shank nails. You can find Roof Sheathing Ring-Shank nails in ASTM F1667, Table 46, and you will see them in the AWC NDS-2018, which will be available at the end of the year. Let us know your preferred fastening practices for roof sheathing.

How Are Deck-Drive™ DWP Screws Load-Rated?

Experiential learning — has it happened to you? Certainly it has, because experiential learning is learning derived from experience. It happens in everyday life, in engineering and in product development, too. For example, experience has taught us that after a product is launched, our customers will find applications for the product that were never expected or listed in the product brief. Also, experience has shown us that larger fasteners tend to be placed in applications that have greater structural and safety demands.

When the larger Deck-Drive™ DWP screws were manufactured, we decided that they should be marketed as “load-rated” screws because they were big enough to support physically large parts and would be expected to provide structural load resistance.

So what is a “load-rated” screw? To Simpson Strong-Tie, a load-rated screw is a threaded fastener that has controlled dimensions and physical properties, as well as validated connection properties.  Load-rated fasteners are also subject to the same quality inspection that would occur if they were undergoing an evaluation report.

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Why You Should Specify Stainless-Steel Screw Anchors When Designing for Corrosive Environments

I was driving under a concrete bridge one nice clear day in Chicago, and I happened to look up to see rusted rebar exposed below a concrete bridge. My beautiful wife, who is not a structural engineer, turned to me and asked, “What happened to that bridge?” I explained that there are many reasons why spalling occurs below a bridge. One common reason is the expansion of steel when it rusts or corrodes.

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What Makes a Good Training Facility?

When it comes to choosing a training facility, there are many well-researched principles about what makes an environment conducive to improved adult learning.

While we try to hold all training events in facilities that meet most of these principles, (even when traveling to our customers or users means we have to conduct events in hotel meeting rooms) we prefer to host you at our own locations.

To this end, we invest a tremendous amount of time and resources to build and offer dedicated training facilities across the country. These facilities meet all the basic requirements for improved adult learning, but much more as well.

By having our own dedicated training facilities, we can provide learners with a much richer experience and contextually relevant displays.

These displays include partially deconstructed wall segments, foundations and roof systems that give learners a bigger picture of the applications being studied.

Many displays allow for hands-on installations and exercises that allow for improved comprehension of the product use and limitations. Even for the engineering community, who typically are limited to images from a catalog, the hands-on activities add great value. It’s always interesting to see the reaction that engineers have to actually seeing a system approach and having an opportunity to participate in learning that goes way beyond sitting and listening to a lecture.

Sometimes learners just need to see, feel or hold something in order to really understand a concept or product application. We make every effort to bring legitimate educational content to our workshops, supported by products that we hope will furnish solutions to your needs.

Many of our facilities include a plant tour and/or testing-facility tour as well. While these components don’t always align directly with the learning objectives, they do offer a chance for our guests to raise their energy levels and get a better understanding of that scale, capabilities, and commitment to quality that we bring to bear in our endeavor to help people build safer structures.

Additionally, we offer our facilities to customers, associations and industry organizations to use for their own meetings and training events. If you haven’t been to one of our workshops or visited one of our facilities, I highly encourage you to join the 35,000 plus who have over the last four years. You can find a complete list of workshops on our training home page. I expect that you’ll find it an educational and highly engaging experience that helps you build safer structures as well.

SST Training Website
SST Training Website

 

Sneak Peek: Our New and Improved Deck Design Guide

One of the ways I get through winter every year is by looking forward to the weekend in March when we set our clocks ahead and “spring forward” into Daylight Savings time. Some people don’t like this change because of the lost hour of sleep, but to me it means the weather shouldn’t be cold for much longer.

The coming of spring means getting to walk to the car in daylight at the end of the workday. It also means getting the garden started for the year and spending more time outside in general.

Of course, I’m not alone in being happy to see winter go.

In the residential world, the phenomenon of “deck season” coincides with this time of year.  Homeowners with decks are getting ready for summer by giving their decks a cleaning and looking them over for any needed maintenance. Now’s the time that new or replacement decks are being planned and built to be enjoyed for the rest of the year.

deck-season

It’s no coincidence, then, that our deck-code guide has been updated again in time for warmer weather. The Deck Connection and Fastening Guide goes detail by detail (ledger connection, joist-to-beam connection, beam-to-post connection, etc.) through a typical deck and identifies the relevant building-code requirements (2012 and 2015 IRC/IBC) and connection options.

Our deck-code guide can be a helpful reference to an engineer who is just getting acquainted with decks, and can also bring you up to speed on revisions to the IRC that can necessitate engineering changes to even a relatively simple residential deck. Multilevel decks, guardrail details, ledger details and foundation challenges are all examples of things a deck builder could call you for assistance with.

For more information on resources available to engineers on deck design, feel free to consult my previous blog article, Wood-framed Deck Design Resources for Engineers.

The Deck Connection and Fastening Guide

F-DECKCODE17

This guide provides instructions on how to recognize defects and deficiencies in existing decks, and guidance for building a strong, safe, long-lasting new or renovated deck structures.


For more deck-related blog posts, check out the links below:

5 Steps to a Successful Soft-Story Retrofit

Last year, I gave a presentation at the annual National Council of Structural Engineers Associations (NCSEA) Summit in Orlando, Florida, titled “Becoming a Trusted Advisor: Communication and Selling Skills for Structural Engineers.” As this was a summit for the leaders of the structural engineers associations from across the country, I wasn’t sure how many people would find it valuable to spend their time learning about a very nontechnical topic. To my surprise and delight, the seminar ended up being standing-room only, and I was able to field some great questions from the audience about how they could improve their selling and communication skills. In the many conversations I had with the conference attendees after my presentation, the common theme was that engineers felt they needed more soft-skills training in order to better serve their clients. The problem, however, was finding the time to do so when faced with the daily grind of design work.

Structural Engineers In a Training for Seismic Retrofits
Presenting at the NCSEA Summit, I’m the tiny person in upper left hand corner.

When I started my first job as a design engineer at a structural engineering consulting firm straight out of school, I was very focused on improving and expanding my technical expertise. Whenever possible, I would attend building-code seminars, design reviews and new product solution presentations, all in an effort to learn more about structural engineering. What I found as I progressed through my career, however, was that no matter how much I learned or how hardworking I was, it didn’t really matter if I couldn’t successfully convey my knowledge or ideas to the person who really mattered most: the client.

Contractors discussing building plans with an engineer.
Contractors discussing building plans with an engineer.

How can an engineer be most effective in explaining a proposed action or solution to a client? You have to be able to effectively sell your idea by understanding the needs of your client as well as any reasons for hesitation. The importance of effective communication and persuasion is probably intuitive to anyone who’s been on the sales side of the business, but not something that occurs naturally to data-driven folks like engineers. As a result of recent legislation in California, however, structural engineers are starting to be inundated with questions from a group of folks who have suddenly found themselves responsible for seismically upgrading their properties: apartment building owners in San Francisco and Los Angeles.

Imagine for a moment that you are a building owner who has received a soft-story retrofit notice under the City of Los Angeles’ Ordinance 183893; you have zero knowledge of structural engineering or what this term “soft-story” even means. Who will be your trusted advisor to help you sort it out? The City of Los Angeles Department of Building and Safety (LADBS) has put together a helpful mandatory ordinance website that explains the programs and also offers an FAQ for building owners that lets them know the first step in the process: hire an engineer or architect licensed in the state of California to evaluate the building.

Simpson Strong-Tie Structural Engineer Annie Kao at a jobsite.
Checking out some soft story buildings in Los Angeles. The Los Angeles Times has a great map tool.

I’ve had the opportunity to be the first point of contact for a building owner after they received a mandatory notice, because it turns out some relatives own an apartment building with soft-story tuck-under parking. Panicked by the notice, they called me looking to understand why they were being forced to retrofit a building that “never had any problems in the past.” They were worried they would lose rent money due to tenants needing to relocate, worried about how to meet the requirements of the ordinance and, most importantly, worried about how much it was going to cost them. What they really wanted was a simple, straightforward answer to their questions, and I did my best to explain the necessity behind retrofitting these vulnerable buildings and give an estimated time frame and cost that I had learned from attending the first Los Angeles Retrofit Resource Fair in April 2016. With close to 18,000 buildings in the cities of San Francisco and Los Angeles alone that have been classified as “soft-story,” this equates to quite a number of building owners who will have similar questions and be searching for answers.

To help provide an additional resource, Simpson Strong-Tie will be hosting a webinar for building owners in the Los Angeles area who have received a mandatory soft-story retrofit notice. Jeff Ellis and I will be covering “5 Steps to a Successful Retrofit” and helping to set a clear project path for building owners. The five steps that Simpson Strong-Tie will be recommending are:

  1. Understanding the Seismic Retrofit Mandate
  2. Partnering with Design Professionals
  3. Submitting Building Plans with the Right Retrofit Product Solutions
  4. Communicating with Your Building Tenants
  5. Completing Your Soft-Story Retrofit

We encourage you to invite any clients or potential clients to attend this informative webinar, which will lay the foundation for great communication between the two of you. As part of the webinar, we will be asking the building owners for their comments, questions and feedback so we can better understand what information they need to make informed decisions, and we will be sure to share these with the structural engineering community in a future post. By working together to support better communication and understanding among all stakeholders in retrofit projects, we will be well on our way to creating stronger and more resilient communities!

For additional information or articles of interest, there are several resources available:

Building Code Update: 2018 IBC to Reference ASCE 7-16

In early December, ICC posted the preliminary results of the Group B Online Governmental Consensus Vote, which included structural changes to the IBC, IEBC and IRC. ICC reports that there were more than 162,000 votes cast by eligible Voting Members during the three-week online voting period.

One subject of interest to building Designers, builders and some building-material suppliers was the disposition of a group of code changes that adopted ASCE 7-16 as the reference standard on loads for the IBC and IRC, and changed other parts of the IBC and IRC to reflect that.

The most controversial part of adopting the new ASCE 7-16 standard was its increase in roof component and cladding loads. The higher pressure coefficients in some cases raised the concern that the cost of roofing, roofing materials and roof repairs would be increased. Other items that raised some opposition were the new chapter on tsunami loads and the increase in deck and balcony live loads from 40 psf to 60 psf.

Despite these concerns, ICC members voted to approve the code change that adopted ASCE 7-16 as the reference for loads in the 2018 IBC, IRC and IEBC.

Along with that specific change, several other related changes were approved to correlate the IBC with adoption of ASCE 7-16. These included changes to Section 1604, General Design Requirements; adding in a new Section 1615 on Tsunami Design Requirements; modifications to Section 1613 so that seismic design requirements match ASCE 7-16; and deletion of Section 1609.6, Alternate All-Heights Method for wind design. On this last item, the argument was that since ASCE 7 now includes a simplified wind load design method, a competing method is not needed in the IBC.

Interestingly, a change to remove Strength Design and Allowable Stress Design load combinations from the IBC, which was approved by the IBC Structural Committee, was overturned and denied by the ICC Member voters. So those will remain in the IBC.

For the IRC, even though ASCE 7-16 will be shown as the referenced load standard, most changes to the actual code language relating to the new standard were denied. Items that were specifically denied included adoption of ASCE 7-16 wind speed maps, adoption of ASCE 7-16 roof pressure loading, and adoption of the new higher deck and balcony live loads. So the result is that the IBC and IRC will again be inconsistent with each other regarding wind design. On the other hand, the new USGS/NEHRP Seismic Design Maps were approved.

Future Code Corner articles will address other changes approved for the 2018 IBC and IRC.

 

3 Hot Tips for Structural Engineers Who Want to Earn Education Credits and Stay Sharp

Do you ever get so busy that you can’t keep up with the structural engineer training opportunities that are available? We have previously shared online resources and webinars that are available to structural engineers, but did you know that you can take advantage of Simpson Strong-Tie regional training centers that offer complimentary workshops and classes about proper specification, product installation and inspection of connectors and structural systems? Here are some tips on staying current with your training.

Simpson Strong-Tie training courses and webinars are focused on improving building standards and the overall safety of structures. With eight training centers across North America, Simpson Strong-Tie provides hundreds of complimentary classes to engineers, architects, builders and code officials each year. In fact, we have trained more than 24,000 participants online and in-person in 2016 alone.

“The workshops are very interactive,” explained Charlie Roesset, Director of Training for Simpson Strong-Tie. “Depending on the course, students may have the opportunity to view product samples or take part in product testing and installations.”

Tip #1 Make Training Offerings Work for You

If you specialize in a specific discipline, look for courses that are targeted to your area of interest or expertise. Simpson Strong-Tie courses include a broad range of topics from anchor system installation and engineered wood frame construction to seismic and high-wind design. We also incorporate the latest building-code updates and industry trends into our training curriculum. No matter where you are in your professional career, we offer a course that’s right for you. There are introductory courses as well as more advanced workshops for repeat and seasoned attendees.

Training participants receive a certificate of attendance with professional development hours (PDHs) at the end of each workshop, and may earn continuing education units (CEUs) and/or learning units (LUs) by completing additional requirements. Simpson Strong-Tie is a registered education provider with a number of industry organizations and associations including CSI, BIA, ACIA, AIBD, ICC, AIA* and IACET**.

Tip #2 Find Trainings That Are Current

Do your research to find workshops and online courses that are regularly updated to reflect changes within the industry. For example, we have regular trainings that focus on the new seismic retrofit ordinances in various municipalities on the West Coast (such as Los Angeles’ Soft-Story Retrofit Ordinance) and others on high-wind design and construction in the Southeast. Our trainings are tailored to your design needs based on your practice’s location.

Full-day workshops typically run from 8:00 a.m. to 4:00 p.m. Classes are often tailored toward specific audiences types to ensure that the training is appropriate and effective. Many courses are team-taught by registered engineers to provide in-depth technical expertise in the subject matter. While much of the instruction is technical in nature, many real-life examples and hands-on demonstrations are provided to help all attendees fully understand the material presented.

Tip #3 Hear What Other Structural Engineers Have to Say

Training

It is always a good sign when others in your field have good things to say about the courses they have taken. Below are some comments past participants have said about our training offerings:

Fred B., S.E., an engineer from Las Vegas, NV, has been a regular attendee of Simpson Strong-Tie workshops. He says the training keeps him informed of topics relevant to his industry and is a great way to keep up with his professional development hours. “Some of the courses offered by other groups are just not that interesting and they can be quite expensive. Simpson programs are interesting, hands-on and free. It’s the whole package.”

Bob N., an engineer from Richmond, VA, wrote, “Keep up the good work; I have found your seminars to be well done, pertinent, and useful. We also specify a lot of your products because of the training and the fact that you have an excellent product line.”

Kathy P., an engineer from Somerville, TX, shares: “You guys are so great! You teach well and keep it interesting. . . . . You support the industry to the benefit of everyone, not just your bottom line, and you make educational credits cost effective. Thank you, thank you, thank you!”

Sign up for a workshop and find out more about Simpson Strong-Tie training programs, including our latest online courses, by visiting www.strongtie.com/workshops.

* Simpson Strong-Tie is registered with the American Institute of Architects, Continuing Education System (AIA CES) as a provider of AIA Learning Units (AIA LUs).

** Simpson Strong-Tie is accredited by the International Association for Continuing Education and Training (IACET) and is authorized to issue the IACET CEU.

Written by Minara El-Rahman in collaboration with the Simpson Strong-Tie Training Department.