Simpson Build Change Fellow Visits Colombia

This week’s post was written by James P. Mwangi, Ph.D., P.E., S.E. — our first annual Simpson Strong-Tie Engineering Excellence Fellow with Build Change. As part of his fellowship, he’s submitting reports about his work supporting the Build Change initiative. This is the third in a series of four.

I spent the final weeks of 2017 finishing my assignment in Colombia before heading back to California, where I worked until the middle of March 2018.

The entire period in Colombia was spent supporting their technical team. My activities included the following:

  • Red-marking Build Change construction details used in conjunction with the Build Change Manual.
  • Addressing and validating the factors used in the design.
  • Using ETABS analysis software to investigate the performance of incremental retrofit in one-story building methods such as these:
    • Building with a heavy (rigid) roof and unreinforced masonry walls
    • Building with a light (flexible) roof with a ring beam and unreinforced masonry walls
    • Building with unreinforced masonry walls with no plaster and either rigid or flexible roofs
    • Building with unreinforced masonry walls with plaster on one side and either rigid or flexible roofs
    • Building with unreinforced masonry walls with plaster on two sides and either rigid or flexible roofs
    • Building with confined masonry walls with either rigid or flexible roofs

Nonlinear time history analysis was conducted using the 1994 Northridge earthquake with a magnitude, Mw = 6.69 and a peak ground acceleration of 0.686g recorded at the Sylmar Station, which is similar to the ground motions expected for Colombia. The performance was evaluated in terms of building stiffness (drifts) to distinguish between immediate occupancy (IO), life safety (LS) or collapse prevention (CP) based on FEMA 356 provisions. The strength was evaluated by analyzing the in-plane shear capacities of the participating masonry shear walls

  • Developing a retrofit card for unreinforced masonry / confined masonry one-story buildings (with heavy and/or light roof) in Colombia.
  • Attending the California Polytechnic’s Architectural Engineering (ARCE) Department Structural Forum where Elizabeth Hausler (Build Change founder and CEO) was the keynote speaker.

Coordinating a meeting between Simpson Strong-Tie engineers in Pleasanton or Chile and Build Change engineers in Colombia or Build Change headquarters to discuss the possibility of using Simpson Strong-Tie® products in the retrofit of informal-housing masonry buildings in Colombia. As things stand, local approval requirements in Colombia may delay the use of such products until a future date.

James with the Build Change team in Bogota, Colombia

L–R: James, Alan Hanson (Simpson Strong-Tie Outreach Coordinator), Allen Estes (ARCE Dept. Head) and Elizabeth Hausler (Build Change Founder and CEO) at ARCE Structural Forum

If you would like more information, please don’t hesitate to contact me at james@buildchange.org to find out in what part of the world I am during the rest of my one-year Build Change fellowship .

Previous Build Change Report:

The post Simpson Build Change Fellow Visits Colombia appeared first on Simpson Strong-Tie Structural Engineering Blog –.

from Simpson Strong-Tie Structural Engineering Blog – http://seblog.strongtie.com/2018/07/simpson-build-change-fellow-visits-colombia/

Advertisements

Happy Independence Day 2018

Thank you for stopping by! We’re taking a brief break today so Simpson Strong-Tie team members can celebrate the Fourth of July with family and friends.

Still here? All right, then, since you’ve scrolled down this far, we may as well give you a sneak peek at an innovation we’re launching later this summer. If you look carefully enough, you can probably see it in this frame from a video we recently shot at our Riverside production plant.

If you want to keep up to date on Simpson Strong-Tie product announcements and other news, be sure to follow us on social media or subscribe to our blogs and newsletters. Or both. Have a safe and fun-filled Fourth!

The post Happy Independence Day 2018 appeared first on Simpson Strong-Tie Structural Engineering Blog –.

from Simpson Strong-Tie Structural Engineering Blog – http://seblog.strongtie.com/2018/07/happy-independence-day-2018/

Roof Framing: Building Strong Roofs

Although truss-designed roofs are predominant throughout most of the residential construction industry, there are regions where building with stick-frame roofs is still common. In this post, Randy Shackelford discusses some design choices available to stick-frame builders, the challenges they pose, and the solutions offered by the Simpson Strong-Tie® three-connector system for stick-frame roofing.

There are two common ways of framing the roof of a house: with premanufactured trusses, or with rafters and ceiling joists, commonly called stick framing. While truss roofs are the most popular construction style today — by some estimates, truss roofs outnumber stick-frame roofs two to one— there are regions of the country where builders still prefer stick-frame roofing. There are several reasons for this. One of the most common is that with a site-built roof, it’s easier to customize the roofline. Builders sometimes also prefer this construction method when they want to provide a large attic space or high, vaulted ceilings (often called cathedral ceilings).

However, constructing a stick-framed roof is not always easy. For example, in Texas where stick framing is common, there are entire crews specializing only in framing roofs. Whether it’s because of the growing size of houses, or because roofs are getting more complicated, the code requirements for stick framing roofs have become more complex over the years, too. Meeting current IRC roof framing requirements means builders are really constructing very simple triangles using the rafters and ceiling joists, because triangles are known to be the most stable shape. In order to maintain the triangle shape, there are specific requirements for how to fasten the corners of the triangle together. Most importantly, the bottom of each triangle (the ceiling joists), must be fastened securely to the rafters on each end and must continue across the entire width of the ceiling so they keep the ends of the rafters from spreading out when loaded. (See illustration.)

Also because of this triangle shape, the connection of rafters to the ridge board is easy because all the weight of the roof is assumed to transfer down to the bearing at the top plate. That’s why the ridge board is nonstructural and can consist of 1x lumber.

However, there are a couple of cases where the bottom leg of the triangles (the ceiling joists) might not be present or might not connect rafters together. The first case is when the ceiling joists are oriented perpendicular to the rafters. The other common case is the cathedral or vaulted ceiling.

The load-resisting concepts of the vaulted ceiling are completely different. Without the tie at the bottom, the rafters must be supported at their upper end to prevent the rafter thrust at the lower end.  Since half the load is now supported at the ridge, the ridge member becomes a ridge beam that is a load-carrying element, and must be designed to bridge the span between the supports, which carry the vertical load to the ground. This requires a secure connection of the rafters to the ridge beam at the top.

Furthermore, if the vaulted roof is constructed as a hip roof, things get even more complicated. Not only must the ridge beam be supported, but the top ends of the hips must also be supported. And the rafters must have a secure connection to the hips.

Simpson Strong-Tie recently developed three products that can greatly simplify the construction of these types of roofs. They’re designed to provide strong, simple connections at three points of the roof that often don’t get the structural reinforcement they deserve.

Rafter-to-Hip or Rafter-to-Valley Connections

The LSSJ field-adjustable jack hanger is the ideal hanger for connecting jack rafters to hip or valley members. The LSSJ is designed with a versatile, hinged seat allowing for easy field adjustment to typical rafter slopes, from 0:12 of 12:12. It’s manufactured with a 45° skew, making it ready to place for the most typical rafter conditions, but it can be field-adjusted for lesser skews. Best of all, it can be installed after the jack rafter is temporarily fastened in place. Note that the LSSJ is available in both right and left skews to cover all the applications.

Rafter-to-Ridge Connections

The LRUZ rafter hanger is an economical sloped hanger for rafter-to-ridge connections. Used with solid sawn rafters, the LRUZ’s design enables the hanger to be installed either before or after the rafter is in place. The field-adjustable seat helps improve job efficiency by eliminating mismatched angles in the field and lead times associated with special orders. The LRUZ offers a load capacity comparable to or better than other rafter hangers’ capacities at a reduced cost while requiring fewer fasteners.

Hip-to-Ridge Connections

The HHRC hip-ridge connector is a heavy, field-slopeable connector that attaches hip and other roof beams to the end of a ridge beam. It accommodates higher loads and uses Simpson Strong-Tie® Strong-Drive® SD Connector screws.

Used in combination, these new connectors make it astonishingly easy to build strong roofs without relying on premanufactured trusses.

Building Stronger Roofs

Learn more about using the Simpson Strong-Tie® three-connector solution for stick-frame roof construction.

Learn More

The post Roof Framing: Building Strong Roofs appeared first on Simpson Strong-Tie Structural Engineering Blog –.

from Simpson Strong-Tie Structural Engineering Blog – http://seblog.strongtie.com/2018/06/roof-framing-building-strong-roofs/

Q&A About Resisting Uplift with Structural Fasteners

Of course you know about creating a continuous load path with either connectors or rod tiedown systems, but have you considered using fasteners instead? In this post, Bryan Wert follows up on our May 2 webinar, Drive a New Path: Resisting Uplift with Structural Fasteners, by answering some of the interesting questions raised by the attendees.

On May 2, Simpson Strong-Tie hosted an interactive webinar where we discussed different methods of creating a continuous load path for wind uplift resistance. Most of the hour-long webinar was devoted to the innovative structural screw system comprising our Strong-Drive® SDWC Truss screw and the SDWF Floor-to-Floor screw with TUW take-up washer. In addition to sharing load capacities, installation details and various benefits of this system, we included a design example with illustrative specification options. In case you weren’t able to join our discussion, you can watch the on-demand webinar and earn PDH and CEU credits here.

As with our previous webinars, we ended with a Q&A session for the attendees. Billy Viars, our Training Manager in the Southeast United States, and Kent Phillips, our Multi-Family Manager, participated in the conversation as well — and since both of these guys love the sound of their own voices, we couldn’t answer every question in the time allotted. Following are a few of the questions and their answers, but if you’d like to see the full list of questions and answers, click here.

Screw Features/Installation/Applications

Does every SDWC screw require a guide?

The SDWC15600 and SDWC15450 both come with one guide in a box of 50 screws or two guides in a bucket of 500 screws. The guide helps ensure the correct angle of installation. Many times, however, the screw can be installed at no particular angle (e.g., roof member to top plate with no stud aligned below) — or, if an angled installation is required, our details allow for a range of acceptable angles for installation in case the guide is not used.

  How much variation in screw placement and installation angle will inspectors accept?

The installation instructions show the acceptable angle range and important end- and edge-distance requirements. You can download them at strongtie.com/products/fastening-systems/technical-notes/installation-detail-drawings.

Can you use impact drivers with these screws?

Yes, this one of advantages for using these fasteners.

Is it all right to use three fasteners per face in 2×4 and 2×6 studs?

We have installation instructions for SDWC screws through the wide face of a stud to plates using one, two or three screws per stud. These studs can be 2×4, 2×6 or 2×8. The maximum number of screws in the wide face of a stud that we’ve tested is two. For three screws, we require two in one face and three in the opposite face.

What is the E-coat on the 4 ½ ” screws? Are these also zinc coated?

The E-coat® on the SDWC15450 is a proprietary coating that consists of a phosphate base and an organic top coating. The coating is recognized for use in some chemically treated woods. The SDWC15600 is zinc coated with an orange topcoat and is limited to dry-service conditions.

Is it ever advisable or necessary to have a second person to guide the screws through the top plate of the wall below?

It should never be necessary. One of the main advantages of the Truss screw is that installing it can be a one-person job. The only difficulty we’ve encountered is that, when installing the screw through a truss with a very steep angle, the installer needs to take some care to ensure that the tip of the screw gets started correctly and does not slide down the web.

Does this have any application in areas that are governed by seismic loads? And why not use a screw down from the bottom plate to a rim board and up from the top plates to a rim board?

The same capacities shown in the tables would apply to seismic loads, since the duration factor for seismic is the same as that for wind (1.60). As far as applications for seismic go, it may be applicable for lightly loaded shearwalls, and the concentrated load capacities of the SDWF-TUW from floor to floor in conjunction with SDWC screws from stud to plate may be useful. And if your second question is asking whether it’s permissible to use SDWC screws to connect either the bottom plate or the top plates (or both) to the rim board, that’s certainly possible if you have an EWP rim board. However, you would have to consider the effects of cross-grain tension if you use a solid sawn rim board; and there are floor systems that exist where you would not have a rim board at all.

Screw System Design / Testing / Load Tables

Are design loads for screws based on testing or just NDS screw withdrawal values?

The values in the load tables presented are based on testing in accordance with ICC-ES Acceptance Criteria 13.

Is Simpson Strong-Tie going to test the SDWC screws for shear connections?

Simpson Strong-Tie has already tested the SDWC for shear connections. The SDWC screw shear connection values are published generally in the evaluation report IAPMO-UES ER-262 (http://www.iapmoes.org/Documents/ER_0262.pdf). For specific shear connections like ledger-to-rim-board and sole-to-rim-board applications, see strongtie.com or our Fastening Systems catalog (C-F-2017).

The tables show F2. What are these values?

The F2 values are lateral shear capacities to transfer load perpendicular to the wall (typically inward or outward wall pressures that must transfer into the floor or roof diaphragms).

Do you have any videos of your testing of these connectors?

We do not have specific video of the SDWC and SDWF testing. However, we do have a good video that discusses and shows our overall testing program that you may find useful. Check it out on our YouTube channel:

Can we use this system for a shear wall instead of the hold down system or Strong-Rod™ system?

We’ve published the concentrated load capacities of the SDWF-TUW in single or double applications. These can be used in conjunction with SDWC screws for stud-to-plate connections for a lightly loaded shearwall holdown. The capacities of holdowns or rod systems are much higher.

Options for Continuous Load Path Uplift Restraint (Connectors, Rods, Fasteners)

Can you provide a cost comparison of the different systems?

There’s a great question that is difficult to give a short answer to. There are many variables that go into determining what the cost really is. The needs of the design and each particular project must be taken into account. Also, each system has its own set of pros and cons, and the value one assigns to each of those is subjective. In addition, there is the issue of cross-scope problems where one person’s scope savings may be another’s expense. Total installed cost regardless of scope should be considered. With all that said, the short answer when looking only at material (not including labor) is this, from lowest cost to highest: (1) connectors; (2) rods; (3) fasteners.

What is the cost advantage of SDWC versus framing angles?

It is literally almost a wash. If you use the street price of a H2.5A versus the SDWC, the screw system appears to be almost twice the price. However, when you include the cost of the 10 nails it takes to install a H2.5A, you almost get that back. Also, the time savings and ease of the screw installation help tilt the balance in favor of the SDWC.

Check out this video showing the time savings associated with installing SDWC screws:

Learn more: Webinar – Drive a new path: Resisting uplift with structural fasteners


After watching the webinar recording, you should be able to:

  • Explain how a threaded fastener system works to establish a continuous load path for uplift restraint
  • Identify threaded fastener solutions for roof-to-wall, stud-to-plate and floor-to-floor connections
  • Describe the benefits of using Strong-Drive structural fasteners compared to traditional continuous load path connection methods
  • Recall design considerations when specifying fastening systems for resisting uplift

Continuing education credits will be offered for this webinar.

  • Participants can earn 1 professional development hour (PDH) or — by passing the accompanying test — 0.1 continuing education unit (CEU).

WATCH NOW!

The post Q&A About Resisting Uplift with Structural Fasteners appeared first on Simpson Strong-Tie Structural Engineering Blog –.

from Simpson Strong-Tie Structural Engineering Blog – http://seblog.strongtie.com/2018/06/qa-resisting-uplift-structural-fasteners/

DWS Timber Screw – The Evolution Continues

Simpson Strong-Tie® R&D engineers are always looking to make products even better and more cost effective, in ways that will improve life not only for homeowners, but also for Designers and builders. In the following post, Aram Khachadourian explains how the newly designed SawTooth™ point on our code-listed Strong-Drive® SDWS Timber screw makes driving faster and easier with no predrilling. The flat head also makes connector and sheathing placement a lot smoother.

It was recently announced that the Strong-Drive SDWS Timber screw has been updated with a newly designed point. You might ask, “Well, what was wrong with the old point?” The short answer is: Nothing. But even when a product has no faults or problems, that doesn’t mean there isn’t room for improvement. Our new and improved Timber screw is the same great structural screw described in IAPMO UES ER-192, but with a new proprietary point.

It was more than twenty years ago that Simpson Strong-Tie changed the fastening world with the introduction of a heavy-duty structural connector screw that could be used in wood construction as an alternative to bolts. That screw, the SDS or Strong-Drive screw, was the first screw of its kind that could be installed without predrilling and get loads comparable to bolts. This made design less complex for engineers and construction easier for contractors. But we didn’t stop there. Over the years we’ve introduced many more structural screws, and made improvements to fastener geometry, heat treatment and coatings. We’ve developed screws to replace bolts in connectors, ledgers, pile construction and more.

The improvements have been both large and small, but all of them have been made to fulfill our mission to help people build safer structures more efficiently — saving time, money and possibly even lives.

The SDWS22 Featuring the SawTooth Point

The new patented point is called the SawTooth™ and improves SDWS performance in two key respects. The first is that it grabs the wood, helping the screw start fast and drive quickly. Occasionally, a builder runs into a piece of wood that’s harder than the others or is using engineered wood with a hard surface. When a hard surface condition is encountered, most screw points will spin around at the surface, grinding away at the wood fibers until one of the threads can finally catch and begin to cut in. We designed the SawTooth point with a sharp angle and serrated threads to penetrate the wood quickly. The threads begin to work right away, pulling the screw in faster without the frustration of waiting for the point to scrape open a hole.

The second performance enhancement we’ve made to the SDWS is to lower the driving torque. Let’s face it, some of these screws are long, and you don’t want to have to fight to keep from being thrown by the drill. The SawTooth point has a cutting knurl built into the point of the screw. This helps open a hole in the wood to receive the threaded length of the screw all while it’s being pulled in by the threads. Having a knurl at the top of the threads helps reduce friction on the shank. The result is a screw that drives with less wear and tear on the installer, the drill motor or the drill battery.

I’ll mention one other aspect of the SDWS Timber screw that-s a favorite among builders — the flat head. Construction isn’t always as simple and clean as it appears in the catalogs. Sometimes you don’t have as much room as you need to fit all the pieces together. The flat head of this screw allows structural connectors to be fitted in place right over the screws. This eliminates having to move things around. One example is a ledger fastened to the rim board with Timber screws, where joist hangers will need to be installed.  The screws fastening the ledger would almost certainly interfere with the placement of the hangers if not for the flat head of the Timber screw, which lets you position the hanger right over the head of the screw. From avoiding hanger interference to allowing installers to put drywall or sheathing right on top of the screws, the flat head of the SDWS makes construction easier.

The SDWS is load rated for use in wood-to-wood and engineered wood connections, ledgers, gypsum applications and much more. It also can be used in exterior conditions and with chemically treated wood, as attested by its corrosion resistance rating in IAPMO UES ER-192. While we believe the Timber screw is in many ways the best screw available on the market today, we’ll continue to look for ways to improve it— because when it comes to screw innovation, we never know when to stop at Simpson Strong-Tie.

The post DWS Timber Screw – The Evolution Continues appeared first on Simpson Strong-Tie Structural Engineering Blog –.

from Simpson Strong-Tie Structural Engineering Blog – http://seblog.strongtie.com/2018/05/dws-timber-screw-evolution-continues/

Best Practices: The Art of the RFI

Nothing will ruin your day faster than getting a call from a builder reporting an issue with trusses you’ve designed.  You hear their frustration as they are faced with a potential delay and additional work to implement a fix.  We all desire to eliminate those calls from our daily business, and one way to do so is to work only on jobs with a perfect set of drawings.  You know, the drawings with dimensions that are 100% correct, have no errors in the listed wall heights, the heel heights are clearly spelled out with the location of the HVAC equipment and lines identified, and every load path is well thought out.  The truth, though, is that there’s really no such thing as a perfect set of drawings, because there will always be some area needing further clarification to ensure the trusses you design won’t have issues.  Although this reality is typically viewed as a source of frustration, it can be an opportunity to provide extra value to your customers by helping them resolve issues before they become a problem in the field.  To do this requires a trained eye to identify issues and the use of an RFI (Request for Information) to work through these issues with the appropriate parties involved.  In this article, we will walk through some best practices of using an RFI to help eliminate those calls.

 When should you use an RFI?

An RFI should be used whenever there is confusion or doubt and more information is needed to accurately complete a project. If the question is asked, “Why do I need to submit an RFI when I can get my information direct?” A simple answer is for the few times when a situation becomes a dispute and multiple parties express opposing accounts of a discussion.

 What format should you use to initiate an RFI?

The general format of the RFI is not as critical as maintaining consistency. The easiest method is to create a format that your entire company can use easily and effectively. This can be as simple as using text editing software or a spreadsheet. If you would like to take it to the next level, there are several construction management software options with built-in tools to make an RFI easier, and even allow tracking through the process.

Write clear and concisely

Be sure to present your RFI in a question format that is clear and concise. It is often better to submit multiple RFIs separately for individual issues rather than to create confusion by combining multiple requests in one submittal. Be specific about the period stakeholders have to answer the RFI before it starts to delay processes. Avoid words or phrases that come across as condescending. Provide clear references to the question through details and images. The easier you make the process the more likely you will get an answer and be able to proceed with your work. Do not hesitate to present possible solutions. As an industry expert, you may have a simple solution that never occurred to anyone else. This type of value will go a long way in building credibility within the community and might even help you win the next job when your reputation as a team player who brings innovative solutions to the table is known.  In some cases, it may be helpful to provide a summary report of all preconstruction RFIs to your customer.

Be sure to include all stakeholders

It is vital to include all individuals that your RFI may affect. Ask that the RFI and its response be communicated to all suppliers and subcontractors that may be affected by the change. For example, if a mechanical unit location has to change due to access issues but no one notifies the HVAC contractor, an entire run of prefabricated ducting or plenums could be incorrect. It is always better to be safe than sorry and sending a few more emails to avoid a potential problem is never a bad idea.

Managing RFIs

One of the most critical elements of an RFI is how submittals and responses are managed. All of the information coming and going needs to be documented and saved.  Often the sheer volume of RFIs can be overwhelming, so be sure and track them using software or hard copies. Most plate and software suppliers provide features to help manage and maintain RFIs in a central location associated to the specific project.

RFI responses that affect pricing

Often, the returned information will affect the original contract price. A best practice is to immediately address any changes that affect pricing with your customer so that there are no surprises down the road. Delaying a response with a price change only communicates that there are no cost changes and everyone proceeds with the project. Job cost changes can be devastating to your business and your design team needs to be cognizant of any changes that can affect the company’s bottom line.

Using an RFI in critical conditions

Finally, the RFI is a tool to bring potential problems to the forefront. As a component manufacturer, once the design task begins, you may uncover conditions that in reality do not really work, or are at the very least, questionable. There may be situations where your experience tells you a certain application for a component may not be the best idea, such as using extreme cantilever conditions or trusses supporting excessive loads where beams could be a better solution. Using the RFI can allow you to express and reference any concerns in a situation that has an unexpected or untenable direction.

We would love to hear your comments or suggestions on best practices for RFIs.

The post Best Practices: The Art of the RFI appeared first on Simpson Strong-Tie Structural Engineering Blog –.

from Simpson Strong-Tie Structural Engineering Blog – http://seblog.strongtie.com/2018/05/best-practices-art-rfi/

Study Shows Effectiveness of Hazard Mitigation Measures

When properly enforced, building codes are very effective for ensuring that buildings meet certain minimal requirements for strength and safety. Recent studies by the National Institute of Building Sciences (NIBS) have shown, however, that additional risk-mitigation measures can be beneficial even in proportion to the added costs. In the following post, Randy Shackelford, P.E., of Simpson Strong-Tie, shares some of the NIBS 2017 study benefit-cost results for two mitigation types — building beyond minimum code requirements, and federal mitigation grants.

Earlier this year, the National Institute of Building Sciences released its updated report on the cost-effectiveness of specific types of measures that various stakeholders can take to reduce the risks from natural hazards. The report is titled “Natural Hazard Mitigation Saves: 2017 Interim Report.”  The report is a sequel to a 2005 study that resulted in the widely quoted statistic that one dollar spent in mitigation results in four dollars saved.

The new report went much further than the previous one by examining the costs and benefits of two types of natural-hazard mitigation activities — building beyond minimum code requirements and federally funded mitigation grants. The effects of these mitigation measures were analyzed for five different natural hazards:  riverine flood; hurricane surge; wind; earthquake; and wildland-urban interface fire. Following is a graphic summarizing results of the report:

The mitigation grants studied are primarily those of the Federal Emergency Management Agency (FEMA), but also include grants from the Department of Housing and Urban Development (HUD) and the Economic Development Association (EDA). For the hazards shown, these federal grants might be for the following purposes:

  • Floods — to acquire or demolish flood-prone buildings
  • Winds — to add hurricane shutters or tornado safe rooms, or strengthen home structures
  • Earthquakes — to strengthen specific structural and nonstructural components
  • Wildfires — to replace wood roofs, manage vegetation or replace wooden water tanks

In examining the effectiveness of building beyond minimum I-Code® requirements, the study looked at each hazard, in each area of the country, and determined what level of mitigation measures provided the maximum bang for the buck. This is called the “incrementally efficient maximum design levels.”  It then calculated the overall benefit if every new building built in one year surpassed minimal code requirements by the level determined to be the most beneficial in proportion to the cost. So the amount that a building exceeds the minimum code requirements might be different in different parts of the country for the same hazard. Further, the study only examined the costs beyond what it would already cost to meet the 2015 IRC or IBC. Later versions of the study will determine the cost-effectiveness of adopting a minimum code where there is not one currently adopted. The following methods were used as “code-plus” for the hazards shown:

  • Riverine flooding and hurricane surge: Build higher than required by code.
  • Hurricane winds: Build to comply with IBHS FORTIFIED Home Hurricane standards.
  • Earthquakes: Build stronger and stiffer than required by the 2015 IBC.
  • Wildfire): Build to comply with the 2015 International Wildland-Urban Interface Code (IWUIC).

The study found that the benefits of building beyond code accrued to all parties involved in the construction process — tenants, title holders, developers, lenders and communities. The table below shows the calculated benefits for the two different mitigation strategies:

New Design to Exceed 2015 I-Code Requirements Federal Mitigation Grants
43% Property 43% Casualties and PTSD
22% Additional Living Expense (ALI) & Business Interruption (BI) 37% Property
13% Casualties and PTSD 7% Insurance
12% Indirect Business Interruption 4% Indirect Business Interruption
10% Insurance 1% Loss of Service

The National Institute of Building Sciences

The National Institute of Building Sciences is a nonprofit, nongovernmental organization designed to support advances in building science and technology to improve the built environment.

 

Download the Full Report

The post Study Shows Effectiveness of Hazard Mitigation Measures appeared first on Simpson Strong-Tie Structural Engineering Blog –.

from Simpson Strong-Tie Structural Engineering Blog – http://seblog.strongtie.com/2018/05/study-shows-effectiveness-hazard-mitigation-measures/